Hi
My conclusion is that this error appeared because of ton of other javascript on website.
On fresh Joomla with only core JS it probably doesn't occur. But on larger websites like ours, with several extra components and modules,
something was clashing. I was able to solve it by removing " from the language phrase.
Unfortunately, CB doesn't use standard language file,
because easiest and most permanent solution would be to create Joomla language override for this phrase.
Using CB language plugin is also an option but it's overkill to do it because of just one phrase, and future CB releases may change own language file so when creating plugin extra work would be needed, to cross-reference original language file with plugin language file after every upgrade.
Anyway I'll just need to have extra line in my check list whenever I Upgrade CB to check file and reapply my change.
Regards