switchable controller actions
See Issue #84990
Links to files that were detected as broken by the system extension
linkvalidator are now marked accordingly in the RTE via
Those links are now marked with extra markup (yellow background with
red border) in RTE.
The procedure for marking the broken links in the RTE is as follow:
The implementation for checking file links is supplied by the system
Other extensions can use the event to override the default behaviour.
The behaviour stays the same as before unless the system extension linkvalidator
If linkvalidator is installed and regularly checks for broken file links, those
links will be marked in the RTE.
If linkvalidator is used, it is recommended to use the scheduler to regularly
check for broken links.