Besides fixing the problem with canvases (possibly suboptimally, but that's better than not fixing it at all) and including the security fixes from 10.0.9, I'm going to go for broke with Barry/Chris' theory on Tenderapp that PostScript Type 1 fonts are the problem for those people who get disappearing or "boxed out" text. Actually, that's not quite the issue -- the issue is fonts that contain only bitmaps and no glyph or CFF information, which includes some TrueType/OpenType fonts as well -- so this version simply ignores those fonts and selects a fallback. The configure settings for Arial, Helvetica and Times remain, just in case. If a font is ignored, it is logged to the Console, so you can run Console.app and see which fonts it believes it cannot render. This doesn't affect downloadable fonts, just the fonts already installed on your system. The moral of this story is, use TrueType and OpenType fonts unless you absolutely have no other way of getting them.
In the Judgment Day department, Tobias' AuroraFox version of 18 has uncovered some unpleasant findings. While the problems with JPEG images and our use of the built-in AltiVec JPEG decoder can be worked around, version 18.0 removes support for QuickDraw plugins, and as a result plugins crash when instantiated on PowerPC in 18.0. I warned you this day would come. Plugin code will be completely disabled in 18.0 to prevent users who have it enabled from being affected. This code will not be restored, and it is unlikely it would work properly even if it were.
Also, for some absolutely ridiculous reason, Josh Aas in what can only be described as an obsession with wrecking functional old code has decided to remove Growl support from 18 also. I don't know how many of you have Growl installed, but I do, mostly for
TTYtter Texapp. However, Firefox and TenFourFox could use Growl to notify users about downloads and updates, and because it was part of toolkit/, it could be used by other Gecko consumers. Allegedly this is being replaced by XUL notifications, but this doesn't even appear to be on the radar. This was a really bad move with half-assed justification, people in the bug weren't too enthusiastic about the idea, and bluntly I'm pretty peeved at him (and I bet people on 10.6 and 10.7 using the real Firefox won't be very happy either, because the only replacement is the Notification Center support which is only in iOS 10.8). We might restore this code if it looks like we have to drop to feature parity between 17 and 24, which is, sadly, probable. I'm curious about how many of you were using Growl, just to see.
QTE update is next.