docs: Publish TOC Election Result 2026 (#38111)

- Adjusted the wording for what happens on a draw (somehow we managed to
get a draw)

The new members are:

- @delvh
- @bircni
- @TheFox0x7

Closes #37551

docs/community-governance.md

@@ -185,17 +185,30 @@ As long as seats are empty in the TOC, members of the previous TOC can fill them
 
 If an elected member that accepts the seat does not have 2FA configured yet, they will be temporarily counted as `answer pending` until they manage to configure 2FA, thus leaving their seat empty for this duration.
 
+If multiple persons have the same amount of votes, a random draw will be used to determine the order of the candidates with the same amount of votes, and thus who gets the seat first.
+The candidates will be placed in the list in an alphabetical insensitive order by their username.
+We use this script to determine the order of candidates with the same amount of votes:
+
+```python
+import random
+random.seed("Gitea TOC <YEAR> Election")
+random.choice([<CANDIDATE_1>, <CANDIDATE_2>, ...])
+```
+
+The result of this script needs then to be published in the TOC election issue to ensure transparency of the process. 
+
 ### Current TOC members
 
-- 2025-01-01 ~ 2026-06-14
+- 2026-06-14 ~ 2026-12-31
   - Company
     - [Jason Song](https://gitea.com/wolfogre) <i@wolfogre.com>
     - [Lunny Xiao](https://gitea.com/lunny) <xiaolunwen@gmail.com>
     - [Matti Ranta](https://gitea.com/techknowlogick) <techknowlogick@gitea.com>
   - Community
-    - [6543](https://gitea.com/6543) <6543@obermui.de>
+    - [bircni](https://gitea.com/bircni) <bircni@icloud.com>
     - [delvh](https://gitea.com/delvh) <dev.lh@web.de>
-    - [lafriks](https://gitea.com/lafriks) <lauris@nix.lv>
+    - [TheFox0x7](https://gitea.com/TheFox0x7) <thefox0x7@gmail.com>
+    
 
 ### Previous TOC/owners members
 
@@ -207,9 +220,10 @@ Here's the history of the owners and the time they served:
 - [Lauris Bukšis-Haberkorns](https://gitea.com/lafriks) - [2018](https://github.com/go-gitea/gitea/issues/3255), [2019](https://github.com/go-gitea/gitea/issues/5572), [2020](https://github.com/go-gitea/gitea/issues/9230), [2021](https://github.com/go-gitea/gitea/issues/13801)
 - [Matti Ranta](https://gitea.com/techknowlogick) - [2019](https://github.com/go-gitea/gitea/issues/5572), [2020](https://github.com/go-gitea/gitea/issues/9230), [2021](https://github.com/go-gitea/gitea/issues/13801), [2022](https://github.com/go-gitea/gitea/issues/17872), 2023
 - [Andrew Thornton](https://gitea.com/zeripath) - [2020](https://github.com/go-gitea/gitea/issues/9230), [2021](https://github.com/go-gitea/gitea/issues/13801), [2022](https://github.com/go-gitea/gitea/issues/17872), 2023
-- [6543](https://gitea.com/6543) - 2023
+- [6543](https://gitea.com/6543) - 2023, 2025
 - [John Olheiser](https://gitea.com/jolheiser) - 2023, 2024
 - [Jason Song](https://gitea.com/wolfogre) - 2023
+- [lafriks](https://gitea.com/lafriks) <lauris@nix.lv> - 2025
 
 ## Governance Compensation
 

main.go

@@ -17,6 +17,7 @@ import (
 	// register supported doc types
 	_ "gitea.dev/modules/markup/console"
 	_ "gitea.dev/modules/markup/csv"
+	_ "gitea.dev/modules/markup/jupyter"
 	_ "gitea.dev/modules/markup/markdown"
 	_ "gitea.dev/modules/markup/orgmode"
 

modules/htmlutil/html.go

@@ -4,6 +4,7 @@
 package htmlutil
 
 import (
+	"errors"
 	"fmt"
 	"html/template"
 	"io"
@@ -88,6 +89,52 @@ func EscapeString(s string) template.HTML {
 	return template.HTML(template.HTMLEscapeString(s))
 }
 
+type HTMLWriter interface {
+	OriginWriter() io.Writer
+	WriteString(s string) HTMLWriter
+	WriteHTML(s template.HTML) HTMLWriter
+	WriteFormat(fmt template.HTML, args ...any) HTMLWriter
+	Err() error
+}
+
+type htmlWriter struct {
+	w    io.Writer
+	errs []error
+}
+
+func (h *htmlWriter) OriginWriter() io.Writer {
+	return h.w
+}
+
+func (h *htmlWriter) WriteString(s string) HTMLWriter {
+	if _, err := io.WriteString(h.w, template.HTMLEscapeString(s)); err != nil {
+		h.errs = append(h.errs, err)
+	}
+	return h
+}
+
+func (h *htmlWriter) WriteHTML(s template.HTML) HTMLWriter {
+	if _, err := io.WriteString(h.w, string(s)); err != nil {
+		h.errs = append(h.errs, err)
+	}
+	return h
+}
+
+func (h *htmlWriter) WriteFormat(fmt template.HTML, args ...any) HTMLWriter {
+	if _, err := HTMLPrintf(h.w, fmt, args...); err != nil {
+		h.errs = append(h.errs, err)
+	}
+	return h
+}
+
+func (h *htmlWriter) Err() error {
+	return errors.Join(h.errs...)
+}
+
+func NewHTMLWriter(w io.Writer) HTMLWriter {
+	return &htmlWriter{w: w}
+}
+
 type HTMLBuilder struct {
 	sb strings.Builder
 }

modules/htmlutil/html_test.go

@@ -5,6 +5,7 @@ package htmlutil
 
 import (
 	"html/template"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -29,3 +30,11 @@ func TestHTMLBuilder(t *testing.T) {
 	assert.Equal(t, "&lt;<hr><span>&gt;&gt;</span>", b.String())
 	assert.Equal(t, template.HTML("&lt;<hr><span>&gt;&gt;</span>"), b.HTMLString())
 }
+
+func TestHTMLWriter(t *testing.T) {
+	sb := new(strings.Builder)
+	w := NewHTMLWriter(sb)
+	w.WriteString("<").WriteHTML("<hr>").WriteFormat("<span>%s%s</span>", ">", EscapeString(">"))
+	assert.Equal(t, "&lt;<hr><span>&gt;&gt;</span>", sb.String())
+	assert.NoError(t, w.Err())
+}

modules/markup/jupyter/jupyter-test.ipynb

@@ -0,0 +1,74 @@
+{
+    "metadata": {},
+    "nbformat": 4,
+    "cells": [
+        {
+            "cell_type": "code",
+            "execution_count": 1,
+            "source": ["print('very-looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong')"],
+            "outputs": [
+                {
+                    "output_type": "execute_result",
+                    "text": ["very-looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong ...\n"]
+                },
+                {
+                    "output_type": "stream",
+                    "name": "stdout",
+                    "text": ["stdout 1 ...\n", "stdout 2 ...\n"]
+                },
+                {
+                    "output_type": "stream",
+                    "name": "stderr",
+                    "text": ["stderr ...\n"]
+                },
+                {
+                    "data": {
+                        "text/plain": ["data text 1\n", "data text 2\n"]
+                    }
+                },
+                {
+                    "data": {
+                        "text/plain": true
+                    }
+                },
+                {
+                    "data": {
+                        "image/svg+xml": ["<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"2000\" height=\"20\"><rect width=\"2000\" height=\"20\" x=\"0\" y=\"0\" rx=\"5\" ry=\"5\" fill=\"red\"/></svg>"]
+                    }
+                },
+                {
+                    "data": {
+                        "text/html": "<a href='/'>HTML Link</a>"
+                    }
+                },
+                {
+                    "data": {
+                        "text/latex": "$$a=1$$"
+                    }
+                },
+                {
+                    "data": {
+                        "text/plain": "plain text"
+                    }
+                },
+                {
+                    "output_type": "error",
+                    "ename": "Error Name",
+                    "traceback": ["stacktrace 1", "stacktrace 2"]
+                }
+            ]
+        },
+        {
+            "cell_type": "unknown-cell"
+        },
+        {
+            "cell_type": "markdown",
+            "source": [
+              "# h1\n", "## h2\n", "### h3\n", "\n", "paragraph 1\n", "\n",
+              "very-looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong\n",
+              "- list item 1\n", "- list item 2\n", "\n", "```python\n", "print('code block')\n", "```\n",
+              "<table><tr><th>th1</th><th>th2</th></tr><tr><td>td1</td><td>td2</td></tr></table>\n"
+            ]
+        }
+    ]
+}

modules/markup/jupyter/jupyter.go

@@ -0,0 +1,393 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package jupyter
+
+import (
+	"encoding/base64"
+	"fmt"
+	"io"
+	"strings"
+	"sync"
+
+	"gitea.dev/modules/highlight"
+	"gitea.dev/modules/htmlutil"
+	"gitea.dev/modules/json"
+	"gitea.dev/modules/log"
+	"gitea.dev/modules/markup"
+	"gitea.dev/modules/markup/markdown"
+	"gitea.dev/modules/setting"
+	"gitea.dev/modules/util"
+)
+
+func init() {
+	markup.RegisterRenderer(renderer{})
+}
+
+// Renderer implements markup.Renderer for Jupyter notebooks
+type renderer struct{}
+
+var (
+	_ markup.Renderer            = (*renderer)(nil)
+	_ markup.PostProcessRenderer = (*renderer)(nil)
+	_ markup.ExternalRenderer    = (*renderer)(nil) // FIXME: this is not an external render, need to refactor the framework in the future
+)
+
+type mimeHandler struct {
+	Mime string
+	Fn   func(w htmlutil.HTMLWriter, data string) error
+}
+
+func renderCellCodeOutputTextPlain(w htmlutil.HTMLWriter, text string) error {
+	w.WriteFormat(`<div class="cell-output-text"><pre>%s</pre></div>`, text)
+	return w.Err()
+}
+
+func renderCellCodeOutputUnsupported(w htmlutil.HTMLWriter, message string) error {
+	w.WriteFormat(`<div class="cell-output-unsupported">%s</div>`, message)
+	return w.Err()
+}
+
+var dataMimeHandlers = sync.OnceValue(func() []mimeHandler {
+	renderImage := func(w htmlutil.HTMLWriter, subtype, payload string) error {
+		w.WriteFormat(`<div class="cell-output-image"><img src="data:image/%s;base64,%s"></div>`, subtype, payload)
+		return w.Err()
+	}
+	renderUnsupportedOutput := func(message string) func(htmlutil.HTMLWriter, string) error {
+		return func(w htmlutil.HTMLWriter, _ string) error {
+			return renderCellCodeOutputUnsupported(w, message)
+		}
+	}
+	return []mimeHandler{
+		// Images (PNG, JPEG, SVG)
+		{"image/png", func(w htmlutil.HTMLWriter, d string) error {
+			return renderImage(w, "png", d)
+		}},
+		{"image/jpeg", func(w htmlutil.HTMLWriter, d string) error {
+			return renderImage(w, "jpeg", d)
+		}},
+		{"image/svg+xml", func(w htmlutil.HTMLWriter, d string) error {
+			return renderImage(w, "svg+xml", base64.StdEncoding.EncodeToString(util.UnsafeStringToBytes(d)))
+		}},
+
+		// Rich & Math Layouts
+		{"text/html", func(w htmlutil.HTMLWriter, d string) error {
+			// To future developers:  don't allow custom CSS classes or attributes,
+			// because ".link-action" or "data-fetch-xxx" can send POST requests and lead to XSS.
+			// If you'd really like to support more, do remember to correctly sanitize the values.
+			w.WriteFormat(`<div class="cell-output-html">%s</div>`, markup.Sanitize(d))
+			return w.Err()
+		}},
+		{"text/latex", func(w htmlutil.HTMLWriter, d string) error {
+			w.WriteFormat(`<div class="cell-output-latex"><pre><code class="language-math display">%s</code></pre></div>`, trimMathDelimiters(d))
+			return w.Err()
+		}},
+		{"text/plain", renderCellCodeOutputTextPlain},
+
+		// Security Placeholders
+		{"application/javascript", renderUnsupportedOutput("[JavaScript output - execution disabled for security]")},
+		{"application/vnd.plotly.v1+json", renderUnsupportedOutput("[Plotly output - interactive plots not supported]")},
+		{"application/vnd.jupyter.widget-view+json", renderUnsupportedOutput("[Jupyter widget - interactive widgets not supported]")},
+	}
+})
+
+func (renderer) Name() string {
+	return "jupyter-render"
+}
+
+func (renderer) NeedPostProcess() bool { return true }
+
+func (renderer) GetExternalRendererOptions() markup.ExternalRendererOptions {
+	return markup.ExternalRendererOptions{
+		// HINT: no need to let markup render sanitize the output because there are many special CSS class names, inline attributes.
+		// This render must guarantee that the output is safe and no XSS
+		SanitizerDisabled: true,
+	}
+}
+
+func (renderer) FileNamePatterns() []string {
+	return []string{"*.ipynb"}
+}
+
+func (renderer) SanitizerRules() []setting.MarkupSanitizerRule {
+	return nil
+}
+
+// Notebook structures
+type Notebook struct {
+	Cells    []Cell         `json:"cells"`
+	Metadata map[string]any `json:"metadata"`
+	Nbformat int            `json:"nbformat"`
+}
+
+type Cell struct {
+	CellType       string         `json:"cell_type"`
+	Source         any            `json:"source"` // string or []string
+	Outputs        []Output       `json:"outputs,omitempty"`
+	ExecutionCount any            `json:"execution_count,omitempty"` // int or null
+	Metadata       map[string]any `json:"metadata,omitempty"`
+}
+
+type Output struct {
+	OutputType string         `json:"output_type"`
+	Data       map[string]any `json:"data,omitempty"`
+	Text       any            `json:"text,omitempty"` // string or []string
+	Name       string         `json:"name,omitempty"`
+	Traceback  any            `json:"traceback,omitempty"` // []string
+	Ename      string         `json:"ename,omitempty"`
+	Evalue     string         `json:"evalue,omitempty"`
+}
+
+// Render renders Jupyter notebook to HTML
+func (renderer) Render(ctx *markup.RenderContext, input io.Reader, outputWriter io.Writer) error {
+	htmlWriter := htmlutil.NewHTMLWriter(outputWriter)
+	// the size is (should be) checked and/or limited by the caller to avoid OOM
+	var notebook Notebook
+	if err := json.NewDecoder(input).Decode(&notebook); err != nil {
+		htmlWriter.WriteFormat(`<div class="ui error message">Failed to parse notebook JSON: %v</div>`, err)
+		return htmlWriter.Err()
+	}
+
+	// Check nbformat version
+	if notebook.Nbformat < 4 {
+		htmlWriter.WriteFormat(
+			`<div class="ui info message">This notebook uses an older format (nbformat %d). Only nbformat 4+ is supported for rendering. Please upgrade the notebook in Jupyter or view the raw JSON.</div>`,
+			notebook.Nbformat,
+		)
+		return htmlWriter.Err()
+	}
+
+	// Detect language
+	language := "python" // default
+	if metadata, ok := notebook.Metadata["language_info"].(map[string]any); ok {
+		if name, ok := metadata["name"].(string); ok {
+			language = name
+		}
+	} else if kernelSpec, ok := notebook.Metadata["kernelspec"].(map[string]any); ok {
+		if lang, ok := kernelSpec["language"].(string); ok {
+			language = lang
+		}
+	}
+
+	// Start rendering
+	htmlWriter.WriteHTML(`<div class="jupyter-notebook">`)
+
+	// limiting the cell rendering to 100 cells
+	cells := notebook.Cells
+	truncated := false
+	const maxRenderedCells = 100
+
+	if len(cells) > maxRenderedCells {
+		cells = cells[:maxRenderedCells] // Slice down to exactly 100 elements instantly at the pointer layer
+		truncated = true
+	}
+
+	for _, cell := range cells {
+		if err := renderCell(ctx, htmlWriter, cell, language); err != nil {
+			log.Warn("Failed to render cell: %v", err) // TODO: RENDER-LOG-HANDLING: see other comments
+			continue
+		}
+	}
+
+	if truncated {
+		htmlWriter.WriteHTML(`<div class="ui warning message">`)
+		htmlWriter.WriteHTML(`<strong>Output truncated.</strong> This notebook contains too many cells to display efficiently.`)
+		htmlWriter.WriteHTML(`</div>`)
+	}
+
+	htmlWriter.WriteHTML(`</div>`)
+	return htmlWriter.Err()
+}
+
+func renderCellCode(output htmlutil.HTMLWriter, cell Cell, language string) error {
+	source := joinSource(cell.Source)
+	var executionCount *int64
+	if cell.ExecutionCount != nil {
+		if count, err := util.ToInt64(cell.ExecutionCount); err == nil {
+			executionCount = &count
+		}
+	}
+
+	output.WriteHTML(`<div class="cell-line">`)
+	{
+		if executionCount != nil {
+			output.WriteFormat(`<div class="cell-left cell-prompt">In [%d]:</div>`, *executionCount)
+		} else {
+			output.WriteHTML(`<div class="cell-left cell-prompt">In [ ]:</div>`)
+		}
+
+		// Highlight code
+		lexer := highlight.DetectChromaLexerByFileName("", language)
+		output.WriteFormat(`<div class="cell-right cell-input"><pre><code class="chroma language-%s">`, strings.ToLower(language))
+		output.WriteHTML(highlight.RenderCodeByLexer(lexer, source))
+		output.WriteHTML("</code></pre></div>")
+	}
+	output.WriteHTML(`</div>`)
+
+	// Render outputs
+	if len(cell.Outputs) > 0 {
+		hasExecutionResult := false
+		for _, out := range cell.Outputs {
+			if out.OutputType == "execute_result" {
+				hasExecutionResult = true
+				break
+			}
+		}
+
+		output.WriteHTML(`<div class="cell-line">`)
+		{
+			if hasExecutionResult && executionCount != nil {
+				output.WriteFormat(`<div class="cell-left cell-prompt">Out [%d]:</div>`, *executionCount)
+			} else {
+				output.WriteHTML(`<div class="cell-left cell-prompt"></div>`)
+			}
+
+			output.WriteHTML(`<div class="cell-right cell-output">`)
+			for _, out := range cell.Outputs {
+				renderCellCodeOutput(output, out)
+			}
+			output.WriteHTML(`</div>`)
+		}
+		output.WriteHTML(`</div>`)
+	}
+
+	return output.Err()
+}
+
+func renderCell(ctx *markup.RenderContext, output htmlutil.HTMLWriter, cell Cell, language string) error {
+	switch cell.CellType {
+	case "markdown":
+		output.WriteHTML(`
+<div class="notebook-cell cell-type-markdown">
+	<div class="cell-line">
+		<div class="cell-left cell-prompt"></div>
+		<div class="cell-right">`)
+		if err := renderCellMarkdown(ctx, output, joinSource(cell.Source)); err != nil {
+			return err
+		}
+		output.WriteHTML(`</div></div></div>`)
+	case "code":
+		output.WriteHTML(`<div class="notebook-cell cell-type-code">`)
+		if err := renderCellCode(output, cell, language); err != nil {
+			return err
+		}
+		output.WriteHTML(`</div>`)
+	default:
+		output.WriteFormat(`
+<div class="notebook-cell">
+	<div class="cell-line">
+		<div class="cell-left cell-prompt">Cell:</div>
+		<div class="cell-right cell-prompt">[Cell type %s - unsupported, skipped]</div>
+	</div>
+</div>`, cell.CellType)
+	}
+	return output.Err()
+}
+
+func renderCellMarkdown(rctx *markup.RenderContext, output htmlutil.HTMLWriter, source string) error {
+	markdownCtx := markup.NewRenderContext(rctx)
+	// make sure the markdown render use the same options and helper to generate correct contents (e.g.: links)
+	markdownCtx.RenderOptions = rctx.RenderOptions
+	markdownCtx.RenderHelper = rctx.RenderHelper
+	output.WriteHTML(`<div class="embedded-markdown">`)
+	if err := markdown.Render(markdownCtx, strings.NewReader(source), output.OriginWriter()); err != nil {
+		return err
+	}
+	output.WriteHTML(`</div>`)
+	return output.Err()
+}
+
+func renderCellCodeOutput(output htmlutil.HTMLWriter, out Output) {
+	if out.Data != nil {
+		// Iterate through our priority list to find the best matching MIME handler available
+		for _, h := range dataMimeHandlers() {
+			if rawPayload, exists := out.Data[h.Mime]; exists {
+				var stringPayload string
+
+				// Flatten the polymorphic JSON input (string or []any) into a single clean string
+				switch v := rawPayload.(type) {
+				case string:
+					stringPayload = v
+				case []any:
+					stringPayload = joinSource(v)
+				default:
+					_ = renderCellCodeOutputUnsupported(output, fmt.Sprintf("[Data output - unsupported data type %T for mime type %s]", rawPayload, h.Mime))
+					continue
+				}
+
+				if err := h.Fn(output, stringPayload); err != nil {
+					// TODO: RENDER-LOG-HANDLING: outputting render's error to sever's log is not a proper approach
+					// The errors can be:
+					// * unsupported element (cell, data, etc): it should render the message on the UI to tell users that the content is not supported, or ignore them if they are ignore-able
+					// * logic error: it should report to server logs
+					// * network error: io.Writer tries to write to the HTTP connection, so the error can also be a network error, such error should be ignored
+					log.Error("Jupyter rendering engine failed for MIME type %s: %v", h.Mime, err)
+				}
+
+				// Return immediately after rendering the top matching priority format
+				return
+			}
+		}
+	}
+
+	// Stream output
+	if out.OutputType == "stream" && out.Text != nil {
+		streamName := util.Iif(out.Name == "stderr", "stderr", "stdout")
+		output.WriteFormat(`<pre class="cell-output-stream stream-%s">%s</pre>`, streamName, joinSource(out.Text))
+		return
+	}
+
+	// Error output
+	if out.OutputType == "error" {
+		traceback := ""
+		if tb, ok := out.Traceback.([]any); ok {
+			lines := make([]string, len(tb))
+			for i, line := range tb {
+				lines[i] = fmt.Sprint(line)
+			}
+			traceback = strings.Join(lines, "\n")
+		}
+		if traceback == "" && out.Ename != "" {
+			traceback = fmt.Sprintf("%s: %s", out.Ename, out.Evalue)
+		}
+		output.WriteFormat(`<pre class="cell-output-error">%s</pre>`, traceback)
+		return
+	}
+
+	// Generic text output
+	if out.Text != nil {
+		_ = renderCellCodeOutputTextPlain(output, joinSource(out.Text))
+	}
+}
+
+func joinSource(source any) string {
+	switch v := source.(type) {
+	case nil:
+		return ""
+	case string:
+		return v
+	case []any:
+		// the "source slice item" has EOL ("\n"), so just join them together
+		parts := make([]string, len(v))
+		for i, part := range v {
+			parts[i] = fmt.Sprint(part)
+		}
+		return strings.Join(parts, "")
+	default:
+		return fmt.Sprint(v)
+	}
+}
+
+// trimMathDelimiters strips a single pair of surrounding math delimiters ("$$...$$" or "$...$"),
+// so the inner expression is handled by the math post-processor. Unlike strings.Trim, it does not
+// eat unrelated "$" characters elsewhere in multi-expression content.
+func trimMathDelimiters(s string) string {
+	s = strings.TrimSpace(s)
+	if t, ok := strings.CutPrefix(s, "$$"); ok {
+		return strings.TrimSuffix(t, "$$")
+	}
+	if t, ok := strings.CutPrefix(s, "$"); ok {
+		return strings.TrimSuffix(t, "$")
+	}
+	return s
+}

modules/markup/jupyter/jupyter_test.go

@@ -0,0 +1,314 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package jupyter
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"gitea.dev/modules/markup"
+	"gitea.dev/modules/test"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRender(t *testing.T) {
+	r := renderer{}
+
+	t.Run("Basic notebook", func(t *testing.T) {
+		input := `{
+			"cells": [
+				{
+					"cell_type": "code",
+					"execution_count": 1,
+					"source": ["print('hello')"],
+					"outputs": [
+						{
+							"output_type": "stream",
+							"name": "stdout",
+							"text": ["hello\n"]
+						}
+					]
+				}
+			],
+			"metadata": {},
+			"nbformat": 4
+		}`
+
+		var output strings.Builder
+		ctx := &markup.RenderContext{}
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+		assert.Contains(t, result, `<div class="jupyter-notebook">`)
+		assert.Contains(t, result, `<div class="notebook-cell cell-type-code">`)
+		assert.Contains(t, result, `In [1]:`)
+		assert.Contains(t, result, `print`)
+		assert.Contains(t, result, `hello`)
+		assert.Contains(t, result, `stream-stdout`)
+	})
+
+	t.Run("Markdown cell with XSS Protection", func(t *testing.T) {
+		input := `{
+			"cells": [
+				{
+					"cell_type": "markdown",
+					"source": [
+						"# Title\n",
+						"Some text\n",
+						"[click me](javascript:alert(1))\n",
+						"<script>alert('dangerous')</script>"
+					]
+				}
+			],
+			"metadata": {},
+			"nbformat": 4
+		}`
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+
+		// Assert normal markup still renders correctly
+		assert.Contains(t, result, `<div class="notebook-cell cell-type-markdown">`)
+		assert.Contains(t, result, `Title`)
+		assert.Contains(t, result, `Some text`)
+		assert.Contains(t, result, `click me`)
+
+		// CRITICAL SECURITY ASSERTIONS: Ensure XSS vectors are completely stripped
+		assert.NotContains(t, result, `javascript:alert`)
+		assert.NotContains(t, result, `<script>`)
+	})
+
+	t.Run("Cell limit truncation guardrail", func(t *testing.T) {
+		// Generate an oversized notebook containing 105 cells dynamically
+		var cellBlocks []string
+		for range 105 {
+			cellBlocks = append(cellBlocks, `{"cell_type": "markdown", "source": ["cell text"]}`)
+		}
+		input := fmt.Sprintf(`{"cells": [%s], "metadata": {}, "nbformat": 4}`, strings.Join(cellBlocks, ","))
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+
+		// Verify it halts rendering gracefully and shows the truncation warning
+		assert.Contains(t, result, "Output truncated.")
+		assert.Contains(t, result, "This notebook contains too many cells to display efficiently.")
+
+		// Count occurrences of the rendered cells to ensure it sliced down to exactly 100 elements
+		assert.Equal(t, 100, strings.Count(result, `class="notebook-cell cell-type-markdown"`))
+	})
+
+	t.Run("Image output", func(t *testing.T) {
+		input := `{
+			"cells": [
+				{
+					"cell_type": "code",
+					"execution_count": 1,
+					"source": ["import matplotlib.pyplot as plt"],
+					"outputs": [
+						{
+							"output_type": "display_data",
+							"data": {
+								"image/png": "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg=="
+							}
+						}
+					]
+				}
+			],
+			"metadata": {},
+			"nbformat": 4
+		}`
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+		assert.Contains(t, result, `<img src="data:image/png;base64,`)
+		assert.Contains(t, result, `iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==`)
+	})
+
+	t.Run("HTML output with style tag", func(t *testing.T) {
+		input := `{
+			"cells": [
+				{
+					"cell_type": "code",
+					"execution_count": 1,
+					"source": ["import pandas as pd"],
+					"outputs": [
+						{
+							"output_type": "execute_result",
+							"data": {
+								"text/html": ["<style scoped>.dataframe tbody tr th { vertical-align: top; }</style><table class=\"dataframe\"><tr><td>1</td></tr></table>"]
+							}
+						}
+					]
+				}
+			],
+			"metadata": {},
+			"nbformat": 4
+		}`
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+		assert.NotContains(t, result, `<style scoped>`)
+		assert.Contains(t, result, `<table><tr><td>1</td></tr></table>`)
+		assert.Contains(t, result, `<td>1</td>`)
+	})
+
+	t.Run("Error output", func(t *testing.T) {
+		input := `{
+			"cells": [
+				{
+					"cell_type": "code",
+					"execution_count": 1,
+					"source": ["raise ValueError('test error')"],
+					"outputs": [
+						{
+							"output_type": "error",
+							"ename": "ValueError",
+							"evalue": "test error",
+							"traceback": ["ValueError: test error"]
+						}
+					]
+				}
+			],
+			"metadata": {},
+			"nbformat": 4
+		}`
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		result := output.String()
+		assert.Contains(t, result, `ValueError: test error`)
+		assert.Contains(t, result, `cell-output-error`)
+	})
+
+	t.Run("Old nbformat version", func(t *testing.T) {
+		input := `{
+			"cells": [],
+			"metadata": {},
+			"nbformat": 3
+		}`
+
+		var output strings.Builder
+		ctx := markup.NewRenderContext(t.Context())
+		err := r.Render(ctx, strings.NewReader(input), &output)
+
+		assert.NoError(t, err)
+		assert.Regexp(t, `<div class="ui info message">This notebook uses an older format.*</div>`, output.String())
+	})
+}
+
+func TestJoinSource(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    any
+		expected string
+	}{
+		{
+			name:     "String input",
+			input:    "hello world",
+			expected: "hello world",
+		},
+		{
+			name:     "Array input",
+			input:    []any{"line1\n", "line2\n", "line3"},
+			expected: "line1\nline2\nline3",
+		},
+		{
+			name:     "Empty array",
+			input:    []any{},
+			expected: "",
+		},
+		{
+			name:     "Single element array",
+			input:    []any{"single"},
+			expected: "single",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := joinSource(tt.input)
+			assert.Equal(t, tt.expected, result)
+		})
+	}
+}
+
+func TestIntegrationAndSanitization(t *testing.T) {
+	// A mock malicious Jupyter notebook containing an XSS injection attempt
+	// inside a text/html output cell (e.g., pretending to be a poisoned Pandas DataFrame).
+	maliciousNotebook := `{
+		"nbformat": 4,
+		"nbformat_minor": 2,
+		"metadata": {},
+		"cells": [
+			{
+				"cell_type": "code",
+				"execution_count": 1,
+				"metadata": {},
+				"source": ["a=1"],
+				"outputs": [
+					{
+						"output_type": "execute_result",
+						"execution_count": 1,
+						"data": {
+							"text/html": [
+								"<div><script>alert('XSS Vector')</script><table class=\"dataframe\"><tr><td>Safe Content</td></tr></table></div>"
+							]
+						},
+						"metadata": {}
+					}
+				]
+			}
+		]
+	}`
+
+	var output strings.Builder
+	ctx := markup.NewRenderContext(t.Context())
+	ctx.RenderOptions.MarkupType = "jupyter-render"
+	err := markup.Render(ctx, strings.NewReader(maliciousNotebook), &output)
+	assert.NoError(t, err)
+	const expected = `
+<div class="jupyter-notebook">
+	<div class="notebook-cell cell-type-code">
+		<div class="cell-line">
+			<div class="cell-left cell-prompt">In [1]:</div>
+			<div class="cell-right cell-input">
+				<pre><code class="chroma language-python">
+					<span class="n">a</span><span class="o">=</span><span class="mi">1</span>
+				</code></pre>
+			</div>
+		</div>
+		<div class="cell-line">
+			<div class="cell-left cell-prompt">Out [1]:</div>
+			<div class="cell-right cell-output">
+				<div class="cell-output-html">
+					<div><table><tbody><tr><td>Safe Content</td></tr></tbody></table></div>
+				</div>
+			</div>
+		</div>
+	</div>
+</div>`
+	assert.Equal(t, test.NormalizeHTMLSpaces(expected), test.NormalizeHTMLSpaces(output.String()))
+}

modules/test/utils.go

@@ -12,12 +12,16 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"os"
+	"regexp"
+	"slices"
 	"strconv"
 	"strings"
 	"sync"
 
 	"gitea.dev/modules/json"
 	"gitea.dev/modules/util"
+
+	"golang.org/x/net/html"
 )
 
 // RedirectURL returns the redirect URL of a http response.
@@ -182,3 +186,48 @@ func ExternalServiceHTTP(t TestingT, envVarName, def string) string {
 	}
 	return val
 }
+
+var normalizeHTMLSpacesRegexp = sync.OnceValue(func() (ret struct {
+	afterRt, beforeLt *regexp.Regexp
+},
+) {
+	ret.afterRt = regexp.MustCompile(`>\s*`)
+	ret.beforeLt = regexp.MustCompile(`\s*<`)
+	return ret
+})
+
+func NormalizeHTMLSpaces(s string) string {
+	vars := normalizeHTMLSpacesRegexp()
+	s = vars.afterRt.ReplaceAllString(s, ">\n")
+	s = vars.beforeLt.ReplaceAllString(s, "\n<")
+	return strings.TrimSpace(s)
+}
+
+func NormalizeHTMLAttributes(t TestingT, s string) string {
+	nodes, err := html.Parse(strings.NewReader(s))
+	if err != nil {
+		t.Errorf("failed to parse expected HTML: %v", err)
+		return ""
+	}
+
+	var normalize func(n *html.Node)
+	normalize = func(n *html.Node) {
+		slices.SortFunc(n.Attr, func(a, b html.Attribute) int {
+			if cmp := strings.Compare(a.Namespace, b.Namespace); cmp != 0 {
+				return cmp
+			}
+			if cmp := strings.Compare(a.Key, b.Key); cmp != 0 {
+				return cmp
+			}
+			return strings.Compare(a.Val, b.Val)
+		})
+		for c := n.FirstChild; c != nil; c = c.NextSibling {
+			normalize(c)
+		}
+	}
+	var sb strings.Builder
+	if err = html.Render(&sb, nodes); err != nil {
+		t.Errorf("failed to render HTML: %v", err)
+	}
+	return sb.String()
+}

routers/api/v1/repo/issue_tracked_time.go

@@ -91,6 +91,7 @@ func ListTrackedTimes(ctx *context.APIContext) {
 		user, err := user_model.GetUserByName(ctx, qUser)
 		if user_model.IsErrUserNotExist(err) {
 			ctx.APIError(http.StatusNotFound, err.Error())
+			return
 		} else if err != nil {
 			ctx.APIErrorInternal(err)
 			return
@@ -499,6 +500,7 @@ func ListTrackedTimesByRepository(ctx *context.APIContext) {
 		user, err := user_model.GetUserByName(ctx, qUser)
 		if user_model.IsErrUserNotExist(err) {
 			ctx.APIError(http.StatusNotFound, err.Error())
+			return
 		} else if err != nil {
 			ctx.APIErrorInternal(err)
 			return

tests/integration/api_issue_tracked_time_test.go

@@ -13,6 +13,7 @@ import (
 	issues_model "gitea.dev/models/issues"
 	"gitea.dev/models/unittest"
 	user_model "gitea.dev/models/user"
+	"gitea.dev/modules/json"
 	api "gitea.dev/modules/structs"
 	"gitea.dev/tests"
 
@@ -61,6 +62,44 @@ func TestAPIGetTrackedTimes(t *testing.T) {
 	assert.Equal(t, int64(6), filterAPITimes[1].ID)
 }
 
+// TestAPIGetTrackedTimesNonExistentUserFilter ensures filtering by a user that
+// does not exist returns a clean 404 instead of panicking (nil pointer dereference).
+func TestAPIGetTrackedTimesNonExistentUserFilter(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	user2 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	issue2 := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{ID: 2})
+	assert.NoError(t, issue2.LoadRepo(t.Context()))
+
+	session := loginUser(t, user2.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeReadIssue, auth_model.AccessTokenScopeReadRepository)
+
+	for _, tc := range []struct {
+		name string
+		url  string
+	}{
+		{"repository level", fmt.Sprintf("/api/v1/repos/%s/%s/times?user=nonexistentuser", user2.Name, issue2.Repo.Name)},
+		{"issue level", fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/times?user=nonexistentuser", user2.Name, issue2.Repo.Name, issue2.Index)},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			req := NewRequest(t, "GET", tc.url).AddTokenAuth(token)
+			resp := MakeRequest(t, req, http.StatusNotFound)
+
+			assert.True(t, json.Valid(resp.Body.Bytes()), "response body must be a single JSON value, got: %s", resp.Body.Bytes())
+
+			var apiError api.APIError
+			DecodeJSON(t, resp, &apiError)
+			assert.Contains(t, apiError.Message, "user does not exist")
+		})
+	}
+
+	t.Run("existing user", func(t *testing.T) {
+		req := NewRequestf(t, "GET", "/api/v1/repos/%s/%s/times?user=%s", user2.Name, issue2.Repo.Name, user2.Name).AddTokenAuth(token)
+		resp := MakeRequest(t, req, http.StatusOK)
+		DecodeJSON(t, resp, api.TrackedTimeList{})
+	})
+}
+
 func TestAPIDeleteTrackedTime(t *testing.T) {
 	defer tests.PrepareTestEnv(t)()
 

tests/integration/html_helper.go

@@ -5,13 +5,12 @@ package integration
 
 import (
 	"io"
-	"slices"
-	"strings"
 	"testing"
 
+	"gitea.dev/modules/test"
+
 	"github.com/PuerkitoBio/goquery"
 	"github.com/stretchr/testify/assert"
-	"golang.org/x/net/html"
 )
 
 // HTMLDoc struct
@@ -53,36 +52,10 @@ func AssertHTMLElement[T int | bool](t testing.TB, doc *HTMLDoc, selector string
 
 func assertHTMLEq(t testing.TB, expected, actual string) {
 	t.Helper()
-	if expected == actual {
+	if expected == actual { // fast path
 		return
 	}
-	exp, err := html.Parse(strings.NewReader(expected))
-	if !assert.NoError(t, err) {
-		return
-	}
-	act, err := html.Parse(strings.NewReader(actual))
-	if !assert.NoError(t, err) {
-		return
-	}
-	var normalize func(n *html.Node)
-	normalize = func(n *html.Node) {
-		slices.SortFunc(n.Attr, func(a, b html.Attribute) int {
-			if cmp := strings.Compare(a.Namespace, b.Namespace); cmp != 0 {
-				return cmp
-			}
-			if cmp := strings.Compare(a.Key, b.Key); cmp != 0 {
-				return cmp
-			}
-			return strings.Compare(a.Val, b.Val)
-		})
-		for c := n.FirstChild; c != nil; c = c.NextSibling {
-			normalize(c)
-		}
-	}
-	normalize(exp)
-	normalize(act)
-	var expNormalized, actNormalized strings.Builder
-	assert.NoError(t, html.Render(&expNormalized, exp))
-	assert.NoError(t, html.Render(&actNormalized, act))
-	assert.Equal(t, expNormalized.String(), actNormalized.String())
+	exp := test.NormalizeHTMLAttributes(t, expected)
+	act := test.NormalizeHTMLAttributes(t, actual)
+	assert.Equal(t, exp, act)
 }

web_src/css/index.css

@@ -52,6 +52,7 @@
 @import "./markup/content.css";
 @import "./markup/codeblock.css";
 @import "./markup/codepreview.css";
+@import "./markup/jupyter.css";
 
 @import "./font_i18n.css";
 @import "./base.css";

web_src/css/markup/jupyter.css

@@ -0,0 +1,93 @@
+.markup.jupyter-render {
+  padding: 0;
+}
+
+.markup .jupyter-notebook {
+  padding: 20px;
+  background: var(--color-body);
+  border-bottom-left-radius: var(--border-radius);
+  border-bottom-right-radius: var(--border-radius);
+  font-family: var(--fonts-monospace);
+  display: flex;
+  flex-direction: column;
+  gap: 2em;
+}
+
+/* cell code */
+.markup .jupyter-notebook .cell-line {
+  display: flex;
+  width: 100%;
+  gap: 0.5em;
+}
+
+.markup .jupyter-notebook .cell-left {
+  width: 100px;
+  flex-shrink: 0;
+}
+
+.markup .jupyter-notebook .cell-right {
+  flex: 1;
+}
+
+.markup .jupyter-notebook .cell-prompt {
+  padding: 10px 0;
+  color: var(--color-text-light-2);
+  font-size: 13px;
+}
+
+.markup .jupyter-notebook .cell-left.cell-prompt {
+  padding-left: 10px;
+  text-align: right;
+  white-space: nowrap;
+  user-select: none;
+}
+
+.markup .jupyter-notebook .cell-right.cell-prompt {
+  padding-right: 10px;
+}
+
+.markup .jupyter-notebook .cell-input,
+.markup .jupyter-notebook .cell-output {
+  overflow-x: auto;
+}
+
+.markup .jupyter-notebook .cell-input pre,
+.markup .jupyter-notebook .cell-output pre {
+  padding: 10px 16px;
+  font-size: 13px;
+  min-height: 40px;
+  margin: 0;
+}
+
+.markup .jupyter-notebook .cell-input pre {
+  background-color: var(--color-code-bg);
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+}
+
+.markup .jupyter-notebook .cell-output {
+  display: flex;
+  flex-direction: column;
+  gap: 1em;
+}
+
+.markup .jupyter-notebook .cell-type-code {
+  display: flex;
+  flex-direction: column;
+  gap: 1em;
+}
+
+.markup .jupyter-notebook .cell-output-unsupported {
+  color: var(--color-text-light-2);
+  font-style: italic;
+  font-size: 13px;
+}
+
+.markup .jupyter-notebook .cell-output-error {
+  color: var(--color-red);
+}
+
+/* cell markdown */
+.markup .jupyter-notebook .cell-right .embedded-markdown {
+  padding: 0 16px; /* match cell code right padding */
+}