What a cool mystery-solving post! I wish all technology writing were this clear and explanatory. For another fun debugging tale, google: Mazda radio Seattle NPR bug
Holy hell lol.
The weirdest bug I've seen yet
251–260 of 334 posts
Re: The weirdest bug I've seen yet
#252Interesting advertisment, but not really a tech article.
Wrong article?
Re: The weirdest bug I've seen yet
#253I gotta say, the ending was pretty disappointing. I was so hyped to learn why Grammarly crashes when Chrome loads a particular gif. What about the gif was different? What part of Grammarly made that happen? I hate to say it but this is modern web dev in a nutshell. Remove stuff until you find where the bug is, tweak it randomly until it's fixed, done. No root cause analysis or anything deep. This is a great post anyw…
> When I removed loader-spinner.gif, the placeholder we display while the menu options load, the page stopped crashing. Eureka! It’s the gif! We swapped in a different gif and the page did not crash.
I would love to have the original and the un-crashy gifs mentioned. It's super easy, generally, and even without an extensive knowledge of image formats to get a grasp of what might be going on and then going down some really exciting rabbit-hole of image encoding/decoding issues.
Just take the two gifs and run them (one by one) through ImageMagick or GraphicsMagick to print out the details of what's in them, and look for differences.
Assuming ImageMagick is installed (or GraphicsMagick) installed, something like:
#imagemagick
$ diff #graphicsmagick
$ diff ...and rabbit-hole away
EDIT: formatting
Re: The weirdest bug I've seen yet
#254I gotta say, the ending was pretty disappointing. I was so hyped to learn why Grammarly crashes when Chrome loads a particular gif. What about the gif was different? What part of Grammarly made that happen? I hate to say it but this is modern web dev in a nutshell. Remove stuff until you find where the bug is, tweak it randomly until it's fixed, done. No root cause analysis or anything deep. This is a great post anyw…
Agreed.
> Unfortunately, with access to neither the Chrome source code nor the Grammarly source code, we can only guess.
Chromium source code is open. They could also certainly try different versions of Chrome to bisect when the issue has started to happen. Isn't there a chance perhaps this crash might actually be disguising a buffer overflow vulnerability as well? Typically user inputs aren't supposed to crash browser/renderer processes.
Re: The weirdest bug I've seen yet
#255I gotta say, the ending was pretty disappointing. I was so hyped to learn why Grammarly crashes when Chrome loads a particular gif. What about the gif was different? What part of Grammarly made that happen? I hate to say it but this is modern web dev in a nutshell. Remove stuff until you find where the bug is, tweak it randomly until it's fixed, done. No root cause analysis or anything deep. This is a great post anyw…
Agreed. > Unfortunately, with access to neither the Chrome source code nor the Grammarly source code, we can only guess. Chromium source code is open. They could also certainly try different versions of Chrome to bisect when the issue has started to happen. Isn't there a chance perhaps this crash might actually be disguising a buffer overflow vulnerability as well? Typically user inputs aren't supposed to crash brows…
They allegedly tried chromium without luck.
Re: The weirdest bug I've seen yet
#256I gotta say, the ending was pretty disappointing. I was so hyped to learn why Grammarly crashes when Chrome loads a particular gif. What about the gif was different? What part of Grammarly made that happen? I hate to say it but this is modern web dev in a nutshell. Remove stuff until you find where the bug is, tweak it randomly until it's fixed, done. No root cause analysis or anything deep. This is a great post anyw…
[deleted]
Re: The weirdest bug I've seen yet
#257Even if you have crash reporting disabled there should be a .dmp generated somewhere in the user profile directory. Manually uploading that to a bug at https://crbug.com/new would allow a Chrome developer to debug it.
If you can't share the dump for similar reasons to why you have crash reporting disabled, you can build minidump_stackwalk from Chromium and use it to generate an unsymbolized stack trace that you can post to the bug. A Chrome developer can then symbolize it.
https://www.chromium.org/developers/decoding-crash-dumps/ has some more details.
Re: The weirdest bug I've seen yet
#258I discovered a bug like this with GIFs too. It turns out some gifs can be encoded such that it is animated and a single frame long.
Can’t remember the exact event name now, but the browser fires a play event when gifs loop.
This particular gif was issuing too many of these play events that made the app super slow and freeze since it was doing some work in those handlers.
We had a bunch of crash reports and bug reports. None of those showed the actual gifs our customers were using. When we asked for the actual gif, we immediately spotted the problem.
Re: The weirdest bug I've seen yet
#259Earlier quoted context omitted.
Isn't it still true in Germany? With the different high school tiers that can even make it impossible to enroll for a university degree? Though you are right that I shouldn't say that Europe as a whole is like Germany or France even if it's sometime easy to assume so haha.
There are different tiers of highschools and different tiers of higher education. The first tiers are more targetted towards craftsmanship (e.g. arithmetic and trigonometry you can quickly do in your head, you start working earlier in life, as early as 16) while the latter tiers are more universal and abstract (e.g. math concepts that have better use for computer science, you start working much later, around 25 years…
Thanks for the details! If you wanted to switch from craftsmanship to say, a more abstract field. Would you have to do the entire 10 years (ish?) of "missed" education?
I know that here in Quebec, you can enroll in university no matter what as long as you are 21 years old and finished high school. Does that happen in Germany? Or is it rare to actually be able to switch between "paths"?
Re: The weirdest bug I've seen yet
#260Spoiler alert But if you read the article... ;@)
Improper animated GIF decoding is potentially a bug and potentially a security vulnerability. The reality is this leads to duck-tape workarounds and greater tech debt on the production side of the web. Sigh. There are standards, there are expectations, there quirks across N implementations, and MxN layers of duck tape in M consuming implementations. Just one implementation intentionally or unintentionally being different causes M headaches.
Also fun Chromium-derived browserisms:
- Updating while open is allowed and leads to silent and not-so-silent breakage.
- MSFT MDE causes unexpected breakage in fun ways every now and then, including the cause of a crash while dragging a tab on Windows.
- Some flavors of Chromium browsers are broken with IPv6 enabled, leading to an ERR_NETWORK_CHANGED on every nth page visit.