Page autocomplete query is getting 403 error

[Frank Vèssia]

Hello, I'm having a strange issue with the page autocomplete asmselect of a page reference field. Out of a sudden is returning a 403 forbidden error when I type something.
From the console I find out the system doesn't like the %= operator, it's the only operator which isn't working, I tried others and the select works.
Any idea why?

Thanks

[Robin S]

Might be mod_security false positive.

 

[Frank Vèssia]

thanks but it's not that unfortunately... ?