Typography settings changes create unexpected revisions

[afercia]

Description

As an user, I would expect Global Styles revisions to be created only when I explicitly click the 'Save' button in the Site editor. As in:

• I'm editing the Site global styles, likely making multiple changes.
• Once I'm done, I click 'Save'.
• I expect a revision to be created only when my edits are complete and after I click Save.
• Instead, revisions may be created while I'm still editing and my changes aren't complete yet.

It appears that saving a change in the Typography settings > Manage fonts modal dialog triggers a 'global save' and thus creates a styles revision. This is unexpected and arguably useful for users. I would want to restore a revision that includes all my changes and not be forced to restore multiple revisions.

Animated GIF to illustrate:

• keep an eye on the 'Save' button behind the modal dialog when Updating fonts settings.
• Observe that after updating fonts settings, there is a new styles revision that only contains the Typography changes.

Step-by-step reproduction instructions

• Go to the Site editor > Styles.
• Change a style e.g. something in the colors.
• Click 'Save' at the top right of the editor.
• Go to Styles > Revisions and observe a new revision has been created with yout color changes.
• Change something in the Typography settings > fonts e.g. disable a font face variant.
• Click 'Update' in the modal dialog.
• While the update is being saved, observe the 'Save' button behind the odal dialog shows a 'saving' state.
• Change something in the color settings again.
• Click 'Save' at the top right of the editor.
• Go to Styles > Revisions and observe two new revision have been created:
  • The last one is about the color change.
  • The previous one is about the font setting change.

Screenshots, screen recording, code snippet

No response

Environment info

No response

Please confirm that you have searched existing issues in the repo.

• [x] Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

• [x] Yes

Please confirm which theme type you used for testing.

• [ ] Block
• [ ] Classic
• [ ] Hybrid (e.g. classic with theme.json)
• [ ] Not sure

[matiasbenedetto]

I think the reason behind this behavior is that the font changes require database updates and filesystem changes in the server in response to user actions (install/uninstall fonts); I remember that when the font library was implemented, delaying these changes until the styles were globally saved while ensuring data coherence seemed more complex and probably not great for user experience either so it was implemented like this.

To reduce the impact of this behavior without complicated changes, maybe we can maintain the auto-save only for install/uninstall operations and disable it for activating/deactivating fonts, as shown in this issue's video.

[afercia]

Thanks for the insight @matiasbenedetto. I do understand the concerns about data coherence, which is a primary concern. On the other hand, I'm not sure the current behavior with the creation of extra, unexpected, revisions is ideal from an user experience perspective. Maybe it could at least be mitigated as you suggested.