Created attachment 256490 [details] backtrace Open a bunch of bugs on Red Hat Bugzilla in new tabs. [1] If you open ~20 bugs, at least one (usually about three for me) should run out of control, allocating memory until your computer begins to swap excessively. Mine hangs for an hour, forcing me to power off. This happens to me multiple times per day. I've found that runaway web processes reach around 5 GiB before they bring down my computer. The issue likely has something to do with the huge combo box with >10000 elements, but I don't know why it does not occur reliably. I've attached a backtrace I took after attaching to a runaway process. It's probably the same issue that was discussed in https://bugs.webkit.org/show_bug.cgi?id=126122
Seems very related to bug #16450.
*** This bug has been marked as a duplicate of bug 16450 ***