Hello, I'm having the same issue on my mac iMac late 2015 Mojave. Every time I open a file in Illustrator it gives me this message, even if I create a new blank A4 document. Furthermore, all Illustrator menus and commands are greyed out and not accessible and the only way to quit is through a force quit. My mac has 32 GB of memory and 500GB of disk space available, so it's definitely not a real memory problem. I tried uninstalling Illustrator and reinstalling it but after a few hours the problem reappeared. I read that hiding the graphic styles panel might prevent the bug from appearing but even if I do it the palette arrangement reverts back to display the graphic styles palette the following time I reboot Illustrator. I see that the last post on this subject is from a month ago... Is this issue being fixed or should I install Illustrator previous version? ... View more