I did! I used the plugin “Ad Inserter” to insert all my HTML codes and that worked! And it saves a lot of time because then you don’t have to manually keep adding Adsense code into every single post.
I tried pasting the code in code view and it is still throwing the JSON error. I used both a Google Adsense code and a FloDesk email form code and they both are throwing the same error. As soon as I delete the Custom HTML block, the page can be saved as normal and is otherwise fine. So it appears to be just the block having the problem? I did an online chat with my host and they couldn’t figure out why the Custom HTML block is having issues either.
I’m having the exact same issue! I’ve tried HTML codes from multiple sources (both Google Adsense and FloDesk), and neither of them works. It is only the Custom HTML of the Block Editor giving me issues. It only started within the last few days. Did you find anything to resolve the issue other than switching to the Classic Editor?