Hi @NinjaTeX,
Please lear all your caching features (plugin, server-side, CDN, and browser’s cache) after updating so that the code from the latest release is always in use.
If clearing cache does not work, please deactivate your caching plugins for a while and do a test for a plugin conflict. You can do this by deactivating all third-party plugins, and seeing if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
Let us know how it goes,
Cheers!