Feature: Disable folder thumbnails by default

[yaira2]

Resolved / Related Issues

• Were these changes approved in an issue or discussion with the project maintainers? In order to prevent extra work, feature requests and changes to the codebase must be approved before the pull request will be reviewed. This prevents extra work for the contributors and maintainers.
  Closes Bug: Icons take a while to display under heavy load #14817...

Validation
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  1. Open app ...
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