Repository: vscode
Issue: Scrolling suggestion docstrings with PgUp/PgDn does not work when only one suggestion
Labels: feature-request,ux,suggest

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**Summary**
Scrolling suggestions' docstrings with PgUp/PgDn works only when multiple suggestions pop up. When only a single suggestion is available (e.g. when the function's name is entered in full), the scrolling with PgUp/PgDn does not work.

**Steps to reproduce**
1. In an editor, in a .py file, type in a recognised identifier that has a long docstring.
2. Ctrl+Space (`Trigger Suggest`) to toggle suggestions.
3. Ctrl+Space (`toggleSuggestionDetails`) to toggle the docstring detail if it is hidden.
4. Ctrl+Alt+Space (`toggleSuggestionFocus`)
5. PgDn to scroll down the docstring. ❌ Nothing happens. (To be precise, PgDn works in the editor mode, i.e. `cursorPageDown`)
![fails](https://user-images.githubusercontent.com/52547519/161657466-4898953c-7986-4c97-b13e-c426921dbd6e.png)

**Expected behaviour**
Everything works as expected when there are multiple suggestions.
1. Type only the first few symbols, so that there multiple possible suggestions.
2. [as above] Ctrl+Space (`Trigger Suggest`) to toggle suggestions.
3. [as above] Ctrl+Space (`toggleSuggestionDetails`) to toggle the docstring detail if it is hidden.
4. [as above] Ctrl+Alt+Space (`toggleSuggestionFocus`)
5. PgDn to scroll down the docstring. ✔ Scrolls as expected.
![works](https://user-images.githubusercontent.com/52547519/161657703-c0789a7b-0efc-47e4-ba5b-43aaa3853f56.png)

**What I tried**
I tried removing `suggestWidgetMultipleSuggestions` condition from the keyboard shortcuts on PageDown, but this alone did not solve the problem.

- Default keybinding: 
![default keybindings](https://user-images.githubusercontent.com/52547519/161657718-b620ac0f-c047-4f5b-b035-25efae6d7099.png)

- Modified keybinding: 
![custom keybindings](https://user-images.githubusercontent.com/52547519/161657741-33aafe36-a02e-4f18-8177-047ebe50c038.png)

**Related**:
- https://code.visualstudio.com/updates/v1_13#_suggestion-list-and-documentation-side-by-side

> For keyboard centric users who want to navigate up and down long documentation, press `Ctrl+Alt+Space` to move the focus to the documentation fly-out such that it can now receive keyboard shortcuts for Page Up/Down actions.

- also https://github.com/microsoft/vscode/issues/46892#issuecomment-402949843 .

**Info**
- Does this issue occur when all extensions are disabled?:
N/A (extensions are required but aren't the problem)
- VS Code Version: 
1.66.0 (user setup)
Commit: e18005f0f1b33c29e81d732535d8c0e47cafb0b5
- OS Version: 
Windows_NT x64 10.0.19042