New revision slider should always allow to see whole note content

[pachlava]

Expected

It should be possible to see the note content completely while checking the revisions.

Observed

If the note is big enough, its final part will be covered by the revision panel.

Reproduced

1. Have a note of decent length (see picture)
2. Open History
3. Scroll to the bottom

• System Make: Mac
• System Model: MBP 16"
• OS: macOS
• OS version: 11.2
• Browser (if applicable): X
• Browser version (if applicable): X
• Simplenote app version: Electron 2.7.0-beta1

[sandymcfadden]

I didn't think about this or #2654 when making these changes.

What do you think of these two issues @SylvesterWilmott?

[SylvesterWilmott]

Agree, the history UI should resize the editor area as opposed to covering it.