#3101: show or hide the sheet tabs and scroll bars of a workbook

Excel can hide the sheet tabs, the horizontal scroll bar and the
vertical scroll bar of a workbook window (File › Options › Advanced ›
Display options for this workbook), saved with the workbook. GridCraft
already read and wrote these settings (#3057) but always showed all
three, and had no command or option for them.

New commands view.showSheetTabs, view.showHorizontalScrollBar and
view.showVerticalScrollBar {on?} (toggling without `on`, undoable,
saved with the workbook), and a "Display options for this workbook"
section in File › Options. The tab bar follows them: without the tabs
the scroll bar takes the bar, without the scroll bar the tabs do, and
with neither the bar isn't shown; without the vertical scroll bar the
grid takes its width.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/ui-parity.md

@@ -1,6 +1,6 @@
 # UI parity
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-11-02 · **Change:** minor (RefEdit reference boxes in dialogs: Goal Seek, Solver and Data Analysis use them, the arrow keys select while a dialog is collapsed and F4 cycles a reference's anchors; earlier: Python cells: Python mode in the formula bar; earlier: Insert › Equation and the equation editor; earlier: every floating object selects, resizes from eight handles and deletes with the keyboard; earlier: Formulas › Error Checking › Trace Error; trace arrows stay through a zoom (#3097); earlier: Page Setup sets the page order, Down, then over or Over, then down, which printing, the print preview, Page Break Preview and Page Layout view follow; earlier: Formulas › Function Library as labelled buttons with category menus; Recently Used and the Insert Function categories; Esc leaves a File-page text field before closing the view; earlier: checkbox cells print as boxes; Ctrl+arrow and Ctrl+Shift+arrow while pointing a formula reference; editing a hyperlink loads its existing fields; AutoSum over a selected row puts its total to the right; ribbon catalog count 276 / 292) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-11-03 · **Change:** minor (Display options for this workbook: sheet tabs and scroll bars; earlier: RefEdit reference boxes in dialogs: Goal Seek, Solver and Data Analysis use them, the arrow keys select while a dialog is collapsed and F4 cycles a reference's anchors; earlier: Python cells: Python mode in the formula bar; earlier: Insert › Equation and the equation editor; earlier: every floating object selects, resizes from eight handles and deletes with the keyboard; earlier: Formulas › Error Checking › Trace Error; trace arrows stay through a zoom (#3097); earlier: Page Setup sets the page order, Down, then over or Over, then down, which printing, the print preview, Page Break Preview and Page Layout view follow; earlier: Formulas › Function Library as labelled buttons with category menus; Recently Used and the Insert Function categories; Esc leaves a File-page text field before closing the view; earlier: checkbox cells print as boxes; Ctrl+arrow and Ctrl+Shift+arrow while pointing a formula reference; editing a hyperlink loads its existing fields; AutoSum over a selected row puts its total to the right; ribbon catalog count 276 / 292) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
 
 Interaction, controls and feel, against Excel. Part of [target-app-parity.md](target-app-parity.md).
 **UI/UX fidelity: ~55% ready, 50–80 h** (estimated). Ribbon command coverage is measured
@@ -237,6 +237,7 @@ scrollbar bugs 2–4 · pixel/feel pass against observed Excel 7–12.
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-11-03 | minor | File › Options › Display options for this workbook: Show horizontal scroll bar, Show vertical scroll bar and Show sheet tabs (`view.showHorizontalScrollBar`, `view.showVerticalScrollBar`, `view.showSheetTabs`), saved with the workbook; with the sheet tabs off the scroll bar takes the bar, with the scroll bar off the tabs do, with both off the bar goes, and without the vertical scroll bar the grid takes its width (#3101) |
 | 2026-11-02 | minor | RefEdit reference boxes in dialogs: pick a range on the grid, collapse the dialog while selecting; Goal Seek, Solver (with the Model Range of Load/Save) and Data Analysis use them; while collapsed the arrow keys move the selection and Shift+arrow extends it, F4 cycles a reference's anchors, a click elsewhere keeps the box picking, a dialog opened over a picking one puts the selection back, OK stays on the sheet its command showed, and scripted cancel and confirm end a pick like the buttons; the dialog's sheet is followed through the recorded undo steps, so a sheet deleted and recreated under its name is not taken for it and an undo of the deletion brings it back; a box the dialog stops showing is no longer picked into |
 | 2026-11-02 | minor | Python mode edits a cell's code in the formula bar's code editor (Ctrl+Alt+Shift+P, `=PY` then Tab, editing a Python cell), with the PY badge beside fx; its keys apply in input order, also several in one frame, and Ctrl+Enter commits through `python.set` (empty code clears the cell), keeping the code and showing the command's message when the code is refused |
 | 2026-11-02 | minor | Insert › Symbols: Equation split button (access keys N E), a gallery of examples, and an equation editor with quick-insert buttons, the error underlined at its position and a live preview; double-clicking an equation edits it |