(Repeatable?) Block over certain content length crashes

While creating a dinner menu block for a restaurant, after the content for the repeatable menu items gets too long, it does not load the preview anymore as well as it becomes uneditable when reloading the page in the editor.

Here is the html from the block editor:

WORKING (shorter content)

https://pastebin.com/xi4xREa0

NOT WORKING (longer content – only the number between 41 and 60 have been added)

https://pastebin.com/mV4F77u7

The number of repeatable items does not seem to matter. Just the length of the meta stored within the html appears to make the difference. Once the content gets too long, it can still save but not anymore be switched into preview or edited when the page gets reloaded in the backend.

When it happens, in the console, the call to

https://pastebin.com/srTWG4Di

shows the following error: Failed to load resource: net::ERR_CONNECTION_CLOSED

Here is the block initialization:

https://pastebin.com/ShS7V4LE

Callback function:

https://pastebin.com/6FE1FPrb

Thank you for checking into this!