Browsing projects at https://projects.archlinux.org/svntogit/packages.git sometimes, but not always, hangs my entire desktop. My lowball guess is that this happens roughly 20% of the time. It can happen on any subpage. This is pretty much the same as Bug #126122, but I have no clue if this is the same problem or a different one. The first warning sign is that the page is taking unusually long to load (3-4 seconds). If I react very quickly and close the tab or my browser, then the day is saved. Otherwise, I can at first move the mouse pointer very sluggishly, but not click on anything, and then I completely lose control. I have no choice but to hold the power button to shut down my computer. I've had no success attempting to debug this, since I don't know how to trigger the bug without borking my computer. webkitgtk3-2.2.3-1.fc20 epiphany-3.10.2-1.fc20
https://projects.archlinux.org/svntogit/packages.git/tree/trunk?h=packages/libreoffice specifically seems to be a fairly reliable reproducer.
*** This bug has been marked as a duplicate of bug 126122 ***
We determined that this issue is most likely related to very large combo boxes. It also is likely to occur on bug reports at bugzilla.redhat.com.
This site got a small redesign and the bug no longer occurs, as far as I can tell.