I have IntelliJ IDEA CE 10.0.3 build #IC-103.255 on Mac OS X Snow Leopard (up-to-date).
When I edit a 1300 lines CSS file, sometimes the editor becomes really slow at typing (any typing sends the CPU to ~95% for half a second to two seconds then back to normal, though I also observe this when it's not slow for typing). The editor for the java files or other (short) stylesheets are not affected, only this one.
Even if I close and reopen the CSS file, the editor stays slow. I have to restart IDEA to get back to normal speed.
Is there a setting I can turn off for this file so that I can edit it normally ?