1. Open a filter (e.g. https://pt.wikipedia.org/wiki/Special:AbuseFilter/138)
2. Press CTRL+F to open the search tool
3. Fill in the find field with anything that is present in the filter e.g. "a"
4. Fill in the replace field with e.g. "b"
5. Replace all ocurrences
6. Save the filter

Expected result
The changes are saved

Actual result
The changes are not saved, even though we can see the code was changed. If I open the JS console in Firefox, I see that $('#wpFilterRules').val() returns the old code instead of the updated version so the code which is highlighted is out of sync with the code in the textarea. I believe the extension should be using the module "jquery.textSelection" for interacting with the textarea.