Experience Editor might fail with a console error similar to one of the following due to parsing ProfileCardsPanel.css as a script:
Uncaught SyntaxError: Unexpected token '.'
Uncaught Error: Script error for: /-/speak/v1/ribbon/ProfileCardsPanel.css
Refused to execute script from '.../ribbon/ProfileCardsPanel.css' because its MIME type ('text/css') is not executable, and strict MIME type checking is enabled
To resolve the issue, download and install the following hotfix:
For Sitecore XP 9.3.0: SC Hotfix 393114-1.zip
Be aware that the hotfix was built for a specific Sitecore XP version, and must not be installed on other Sitecore XP versions or in combination with other hotfixes. In case any other hotfixes have already been installed on a certain Sitecore XP instance, send a request for a compatibility check to Sitecore Support.
Note that the ZIP file contents need to be extracted to locate installation instructions and related files inside. The hotfixes must be installed on a CM instance and then synced with other instances using standard development practices.