Our readers in Quebec may want to temper their excitement for any upcoming Lollipop updates. According to this lengthy thread on Google's Android issue tracker, a number of French-speaking users are seeing system-breaking bugs. When setting an Android 5.0 device's language to Canadian French, it will periodically experience a SystemUI crash, usually when plugged in to charge or sync. The problem only seems to be affecting those who select "Français (Canada)," not "Français (France)."
So far users on the Nexus 5, Nexus 7 2013, and Nexus 9 are experiencing this problem, all running release builds of Lollipop. For some, unplugging the phone resolves the constant crashing of the SystemUI app, and the phone or tablet is once again usable. You can also set the language to just about anything else; since most French Canadians are bilingual, US English seems to be the preferred option at the moment. The issue isn't universal - we'd be seeing hundreds or thousands of complaints if it was, and I can't replicate it on my Nexus 5 test phone.
Google is aware of the issue. As far back as November 13th, Google employees have commented on the thread, indicating that this is a bug that has appeared in previous builds and was fixed, but re-appeared in the latest ones. Three separate issues have been merged into the current thread (#79257), the latest being three days ago. So, expect a fix for this problem soon... but probably not soon enough for those who are experiencing it.
Source: code.google.com - thanks, JF!