There just has been another patch to address this.
Please update your game again.
Unfortunately, besides the statement on the forums (linking for anyone not aware of it: https://forums.thesims.com/en_US/discussion/958413/custom-text-affected-by-the-4-16-update/ ) there's not other information. EA/Maxis rarely gives an ETA on fixes in case something doesn't go as planned.
Guess all you can do is wait ☹️
As @burin077 says, some stuff has already been updated despite the announcement of EA and maybe more will come before it gets fixed again by EA/Maxis.
So, the rare case has happened and Graham made another statement about this on twitter yesterday
They are targeting a fix for Friday
https://twitter.com/SimGuruGraham/status/1118671402100375552
