I have existing filters that I need to edit but when I try to edit any filter, the textbox for the JQL query is missing. Shouldn't the textbox or simple query editor controls appear in the red box in the screenshot below?

I get the same result when navigating from the "Issues" dropdown menu or clicking "Edit Filter Query" under a board configuration. I have tried creating new filters and editing thoses with the same result. I have tried with and without administrative privileges and with a non-admin login. The problem persists in both Edge and Chrome (edit: and Firefox).
Any help would be appreciated. Thanks!
Edit:
Checking dev tools, there are a few divs with "hidden" in the class. Removing these shows and enables the advanced filter box, but the filter cannot be saved.