PT-4575: Per-pane content zoom — chords, opt-in, tab menu, Settings, editor

.context/research/paratext-9-features/00_Master_Feature_Index.md

@@ -1,8 +1,8 @@
 # Paratext 9 - Master Feature Index (v2)
 
-**Version**: 3.8
-**Date**: January 22, 2026
-**Total Features**: 152 features across 16 categories
+**Version**: 3.9
+**Date**: September 15, 2026
+**Total Features**: 153 features across 16 categories
 **Methodology**: Six-source validation (MS, FR, R, M, H, C)
 
 ---
@@ -59,6 +59,7 @@
 | 1.15 | Autocorrect | MS C |
 | 1.16 | Text Normalization Utilities | MS |
 | 1.17 | Editor Real-time Validation | MS M H C |
+| 1.18 | Pane Zoom | MS H C |
 
 ---
 
@@ -442,6 +443,7 @@
 - **Offline Support** → 16.7
 
 ### P
+- **Pane Zoom** → 1.18
 - **Parallel Passages Tool** → 9.2
 - **Paratext Live (Real-time Collaboration)** → 10.3
 - **Plugin System** → 14.1
@@ -536,13 +538,13 @@
 ## Statistics
 
 - **Total Categories**: 16
-- **Total Features**: 152
+- **Total Features**: 153
 
 **Features by validation level:**
 - 6 sources: 23 features
 - 5 sources: 27 features
 - 4 sources: 36 features
-- 3 sources: 28 features
+- 3 sources: 29 features
 - 2 sources: 18 features
 - 1 source: 20 features
 
@@ -552,6 +554,7 @@
 
 | Ver | Date | Changes |
 |-----|------|---------|
+| v3.9 | 2026-09-15 | Added 1.18 Pane Zoom (≡ Tab > View > Zoom; `FocusedPaneZoom`/`SecondaryViewZooms`, `FormZoomer`, `HtmlZoomHelper`, `DefaultZoomMemento`, `CommentListForm` body zoom) and corrected 2.3's "Font size and zoom controls" bullet, which pointed at the project font size rather than at pane zoom; total now 153 features |
 | v3.8 | 2026-01-22 | Validation pass: fixed 13.10 sources (added C); updated statistics |
 | v3.7 | 2026-01-22 | Added 2.10 Vertical Script Support based on source code analysis (supports traditional Mongolian and other vertical scripts); total now 152 features |
 | v3.6 | 2026-01-22 | Added 3 features from HelpData coverage audit: 2.9 Encoding Converter, 11.9 Translation Priorities; expanded 13.10 Project Conversion (MS→MS FR H); total now 151 features |

.context/research/paratext-9-features/01_Translation_Workspace.md

@@ -1143,6 +1143,60 @@ investigation):
 
 ---
 
+### 1.18 Pane Zoom (View > Zoom)
+
+**Description**: Scale the text of the focused pane of a text window without changing the window's chrome, menus or toolbars. Zoom is per pane, not per window: the footnote pane of a Scripture text window keeps a zoom of its own, and the level is remembered per project and per window type between sessions. This is the display-size control users reach for; it is distinct from the project font size set in Language Settings (2.3), which is a project-wide property of the text itself.
+
+**Sub-Features**:
+- Zoom in / zoom out / actual size on the focused pane, from the ≡ Tab > View > Zoom menu and from Ctrl + Plus / Minus / Zero
+- Discrete zoom steps (0.25× through 4.0×) with the current percentage shown in the menu
+- The Scripture text window's footnote pane zooms separately from its text pane
+- The level is remembered per project and per window type, and restored when the window reopens
+- Comment/note list windows zoom their HTML body the same way
+
+**Sources**:
+
+| Source | Reference | Status |
+|--------|-----------|--------|
+| Menu Structure | Menu: `≡ Tab > View > Zoom`; Item: `zoomToolStripMenuItem` (a `ZoomMenuItem`); Owner: `TextForm` | `[MS]` |
+| HelpData | Keyword: "How do I change the size at which a text is displayed?" | `[H]` |
+| Code | `IZoomable` implemented by the zoomable windows; `FormZoomer` interprets the keyboard chords; `DefaultZoomMemento` persists the level | `[C]` |
+
+**Implementation**:
+
+| Depth | File | Found Via | Evidence |
+|-------|------|-----------|----------|
+| 0 | `Paratext/TextForm.Designer.cs` | Menu Structure | `zoomToolStripMenuItem = new Paratext.Base.MegaMenu.ZoomMenuItem()`, `Text = "Zoom"`, `ShortcutKeyDisplayString = "Ctrl + Plus/Minus/Zero"` |
+| 0 | `Paratext/TextForm.cs` | Owner of D0 | delegates `Zoom` to `uiScriptureEditor.FocusedPaneZoom`; saves and restores `SecondaryViewZooms` |
+| 1 | `ParatextBase/MegaMenu/MegaMenu.cs` | Hosts D0 | `IZoomable zoomProvider`, the `zoomSteps` ladder (0.25 … 4.0), `ZoomString` for the displayed percentage |
+| 1 | `ParatextBase/MegaMenu/ZoomMenuItem.cs` | Class of D0 | the menu item itself |
+| 1 | `PtxUtils.UI/IZoomable.cs` | Interface in D0/D1 | the `Zoom` contract every zoomable window implements |
+| 1 | `PtxUtils.UI/Winforms/FormZoomer.cs` | Keyboard path | `ZoomAction { Larger, Smaller, Actual, NoAction }`, `InterpretKeyCode(Keys)` |
+| 1 | `ParatextBase/ScriptureEditor/UsfmMultiPaneControl.cs` | Field in D0 | `FocusedPaneZoom` (the focused pane), `SecondaryViewZooms` (the footnote pane's own levels) |
+| 2 | `ParatextBase/ScriptureEditor/UsfmSinglePaneControl.cs` | Owned by D1 | regenerates the pane stylesheet per zoom via `usfmXhtmlConverter.GetCss(Zoom, …)` |
+| 2 | `HtmlEditor/HtmlZoomHelper.cs` | HTML-hosted windows | `Setup(IHtmlEditorAdaptor, IZoomable)`, `ZoomChanged` — the zoom path for HTML-rendered bodies |
+| 2 | `ParatextBase/DefaultZoomMemento.cs` | Persistence | `SaveZoom(ScrText, formName, zoom)`, `GetZoom(ScrText, formName)`, `ResetZoom(ScrText)` over a `SerializableDictionary<string, double>` |
+| 2 | `Paratext/TextFormMemento.cs` | Persistence | `Zoom` and `SecondaryViewZooms` restored with the window |
+| 2 | `Paratext/ProjectComments/CommentListForm.cs` | Variant | implements `IZoomable` and zooms its list body through `HtmlZoomHelper.Setup(listControl.HtmlEditor, listControl)`; persisted in its own memento |
+
+**UI Entry Points**:
+- ≡ Tab > View > Zoom (shows the current percentage; zoom in / out / actual size)
+  - Menu Structure: `TextForm`, item `zoomToolStripMenuItem`
+  - File: `Paratext/TextForm.Designer.cs`
+- Ctrl + Plus / Ctrl + Minus / Ctrl + 0 on the focused pane
+  - File: `PtxUtils.UI/Winforms/FormZoomer.cs`
+
+**Related Features**:
+- 1.1 Text Editor - the panes that zoom
+- 1.2 Editor Views - zoom applies to every view mode
+- 1.11 Insert Footnotes & Endnotes - the footnote pane that zooms separately
+- 2.3 Font Management (OpenType/Graphite) - the **project** font size, a different control; zoom scales on top of it
+- 10.4 Project Notes - the comment/note list windows that zoom their HTML body
+
+**Validation**: [MS] - - - [H] [C] — Last verified: 2026-09-15
+
+---
+
 ## Cross-References
 
 **Related Categories**:
@@ -1175,6 +1229,7 @@ investigation):
 | 1.15 Autocorrect | ✓ | - | - | - | ✓ | ✓ | 2026-01-20 |
 | 1.16 Text Normalization | ✓ | - | - | - | - | ✓ | 2026-01-21 |
 | 1.17 Editor Real-time Validation | ✓ | - | - | ✓ | ✓ | ✓ | 2026-01-22 |
+| 1.18 Pane Zoom | ✓ | - | - | - | ✓ | ✓ | 2026-09-15 |
 ## Notes
 
 - FormattedEditor is at repo root (`FormattedEditor/`), not under `Paratext/`

.context/research/paratext-9-features/02_Language_Writing_System.md

@@ -4,7 +4,7 @@
 **Focus**: Keyboards, fonts, locale data, Unicode handling  
 **User Roles**: All users (configuration by administrators)  
 **Manual Chapters**: 4 (Keyboarding)  
-**Last Updated**: 2026-01-22
+**Last Updated**: 2026-09-15
 
 ---
 
@@ -130,7 +130,9 @@ Language and writing system features enable Paratext to support the world's lang
 - Graphite font rendering (SIL Graphite)
 - Per-project font assignment
 - Font feature configuration
-- Font size and zoom controls
+- Per-project font size (the project-wide text size set here; the per-pane display zoom is a separate control — see 1.18 Pane Zoom)
+
+> **Not the same as zoom.** This dialog sets the project's font and font *size*, a property of the project that travels with it. Scaling what one pane shows on screen is a separate feature — ≡ Tab > View > Zoom, remembered per pane and per project — catalogued as **1.18 Pane Zoom** in `01_Translation_Workspace.md`.
 
 **Sources**:
 
@@ -181,7 +183,7 @@ Language and writing system features enable Paratext to support the world's lang
 **HelpData Items**:
 - ID: `1af5d594-c397-4cc4-be27-5e88759c6d27` - "How do I change the font used for my project?"
 - ID: `0b4bf85c-5cc8-428c-960c-f610f1796ad6` - "How do I choose font features for Graphite fonts?"
-- ID: `7e6a26d9-899a-4a6f-b3b8-aca642044750` - "How do I change the size at which a text is displayed?"
+- ID: `7e6a26d9-899a-4a6f-b3b8-aca642044750` - "How do I change the size at which a text is displayed?" (display size — see 1.18 Pane Zoom)
 - ID: `63426c4c-a463-4718-b80e-fc875c0e8507` - "Guide: Project > Project settings > Language settings: Font"
 - Dialogs: `LanguageSettingsForm_tabFont`, `LanguageSettingsForm_tabGraphite`