I am filing this as a sibling issue to #3995
In the WP dashboard, the "Welcome to WordPress!" block can be dismissed (per user), via a link at the top-right:

We should introduce such a feature as well; perhaps in a way that it can be reused by other blocks too.
GitHub Issue #:
3996
Recent comments
This is good enough, but maybe the module maintainer would like to add such a feature.
specific webform permissions
This should be allowed atleast on private files directory. Accepted your answer though.
How to upload js and gz files
This is a security precaution. It's not recommended and it's not documented in the settings.php file, but you can set allow_insecure_uploads to be TRUE if you wish to allow uploading files like...
How to upload js and gz files