Created attachment 303069 [details]
Webarchive of vorke.com/products/vorke-z3 plus two screenshots
I downloaded Leopard-webkit from this link:
Version is r210430
I tried it out and it seemed it worked, so I re-linked my Safari 5.0.6 (PPC) to it.
I got a tremendous performance boost plus I can now access all the HTTPS sites I previously could not access, but it was like some content was missing.
Today (20170301) I found proof and I compared the original Safari with the relinked Safari.
On this website...
... there is a box under "Specification"; this is supposed to contain an image which looks like a table, but the image is not being displayed.
At first I thought this was a Layout and Rendering bug, but it might be something else, because the missing content is an image, not text.
If I load the attached webarchive into the original Safari 5.0.6, it looks like expected.
If I load the attached webarchive into the relinked Safari 5.0.6, the image is missing.
(This webarchive is saved using the original Safari 5.0.6, but even if I saved from the relinked Safari it still shows alright in the original Safari).
Hardware: PowerMac G5, 2.5 GHz Quad-core with 2 x 2TB HDD in RAID0 configuration and 10 GB RAM.
System: Mac OS X 10.5.8
Safari version: 5.0.6
Relinked Safari: 5.0.6 relinked with r210430
Note: I cannot run any later operating system than Mac OS X 10.5.8 and I cannot run any later version of Safari than 5.0.6.
This is of course not a supported configuration, but I can reproduce with trunk on macOS 10.12. Works in Chrome.
Looks like some bad interaction between opacity and opacity transition.
Can't use Web Inspector to inspect CSS, filed bug 169041.