Display no longer functions correctly after update

Question

After updating this morning (the only package updated being wayland), the display on my main computer (laptop still works fine) no longer works properly. It is a bit difficult to describe the problem: there is a constantly changing display of symbols in various colours, "behind" which the usual terminal messages are still legible, though a bit garbled. This began right after re-boot following the update. Because the problem is apparent immediately when the display starts with the manufacturer's logo, I thought at first my monitor had given up. But the same problem occurs on a replacement monitor, which leads me to think it is a software problem. Any hints -- or even better -- a solution? X won't start, making it pretty useless. I can still ssh into it from my laptop, but a real solution is required. My graphics card is NVidia, if that matters (Intel on my laptop).
Many thanks!
Thea
PS I should add, I have read other posts from today regarding similar display issues, and this one appears to be different, although perhaps related. I retrograded the wayland package, but the problem remains. Wayland was the only package I updated-- that is, the only difference between pre-update (no problems) and post-update (dispaly does not work properly).
PPS further details:
1. The problem is already apparent at start-up (push the ON button): the computer (not the monitor) manufacturer name appears, but the display is in dashed lines.
2. After Arch Linux boot and login, there are 5 vertical bands each about 4cm (1.5 ") wide of "shimmering" pixel colour squares spaced evenly across the screen, the intervening spaces are "normal" -- that is, display correctly and without problem. So to some extent, still workable. X will not start, giving me an error message:(/var/log/Xorg.0.log)
NVIDIA: Failed to initialize the NVIDIA kernel module
with the advice to consult kernel.log. However, this log (and all other kernel logs) is empty.
3. When the monitor goes into standby mode, the "shimmering" bands are still visible.
Update 1:
After mesa update this afternoon (21 Feb.) video display returned to normal (ok, mesa depends on wayland) until trying unsuccessfully to start X. Since then (and also after a couple of reboots) the problem is the same. Am hoping the silence on this issue indicates that work is in progress in fixing it.
Update 2:
After a night in a cold office (I live in southern Ontario) and a literally cold boot (but no updates), everything appears to be back to normal.
Still, it would be nice to know what the problem was.
Update 3:
So much for magic. This morning (23 Feb.) after normal system update (no obvious problematic packages relating to graphics) the display oroblem returned, as before. Fresh boot made no difference. What's going on??
Am re-posting this as a new message. Monday, start of the week, who knows, maybe someone can help.
Last edited by thea (2015-02-23 14:38:28)

Answer 1

You are probably better discussing web design elsewhere such as on http://forums.mozillazine.org/viewforum.php?f=25
There have been changes in Firefox as documented for example
* https://developer.mozilla.org/en-US/docs/Firefox_15_for_developers
* https://developer.mozilla.org/en-US/docs/Firefox_16_for_developers
Is the website/application a publicly available one if so are you able to provide a link. Otherwise maybe post an example of code that is affected.
You may also wish to check the code for validity with for instance http://validator.w3.org/