Appearance - limited number of changes

Summary

When working the branding under Appearance in a custom theme, we are facing something like a "number of changes limit" and no more changes can then be applied.

Content

Hello Community,

Our Marketing team is working the branding in a dev instance, and this activity includes multiple iterative changes in the same sandbox.

But the system behaviour does not allow (example given) more than 2 different uploads of a logo - the 3rd version of the logo won't be applied, not matter what we do (come back to the Default theme, then come back to the custom theme, delete the theme and restart from scratch, etc).