Content area goes black on all tabs
Linux Mint 17 Qiana, 16gb RAM, Core i5-3570 CPU @ 3.40GHz. ATI Radeon HD6670
Upgraded to the new version a while ago (V26?) & it functioned OK.
Recently, on occasions, all the open tab content areas have gone black. If I shutdown & restart all is OK, but this is no way to continue.
I've also just discovered that one set of tabs are blank (white). In most cases, the System & tab bars are present but on one (of 3) windows it is all black apart from the page title at the very top.
It first happened when I had 90 tabs open + other programs & I wondered if it was a memory issue, but I now have 69 & nothing else running.
If I search for "black" anything, I've only found stuff IRO video/youtube, which this is not.
Can anyone offer any helpful advice please?