Error with panel textarea


I’ve got a weird bug in the panel with the textarea field when saving data. Sometime I’m enable to save a piece of text, I’ve got the pop-up error “An unexpected error occurred”

I don’t understand what type of text causes the error. For instance, at the moment, I’ve got an error if I add the text:

11. Who having received or being receiving

But if I try these text combinations, it works, I can save the page.

11. Who being receiving or having received
11. Who having received or 
11. Who having received being receiving
11. Who having or received being receiving

I can’t reproduce this bug with the last Starterkit so there is probably a conflict with a piece of code in my website.

Do you have any idea what could cause this bug?

First of all I’d remove all plugins (if any) and then re-add them one by one to see if you can find out which one might be causing this issue.

I will try but for some plugins, it could crash my website because blueprint or snippets/controller could use specific plugin function or fields …

Then I’d first check if this issue appears in every page with a textarea field or only when it comes to blueprints that use plugins.