Bug 262078

Summary: [mac] WebDriver sometimes taking screenshots with transparent grey line at the top and no rounded corners
Product: WebKit Reporter: Sam Sneddon [:gsnedders] <gsnedders>
Component: WebKit Misc.Assignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Bad screenshot from the first example
none
Good screenshot from the first example none

Description Sam Sneddon [:gsnedders] 2023-09-25 16:00:20 PDT 
see, e.g., https://wpt.fyi/results/css/css-contain?q=%28label%3Ainterop-2022-contain%20or%20label%3Ainterop-2023-contain%29%20is%3Adifferent&run_id=5179945829007360&run_id=5129256222326784&run_id=5105446492307456

e.g. https://wpt.fyi/analyzer?screenshot=sha1%3Aa8193aa1d36a2e7c269c79da3fdfef70d986dd6d&screenshot=sha1%3A1bc22df9e9199ea9890c7d35fbf48b11b87cf11b or https://wpt.fyi/analyzer?screenshot=sha1%3A8d5e20aecf8b5cc808f48b90c8ee7e09f88d3c38&screenshot=sha1%3Abc778655cc0444e393609feb97a0948c43475817

We seem to end up with a transparent grey overlay at the top (the shadow from the tab bar?), one pixel high. What's more odd given that is we also are lacking the rounded corners we'd expect from the window, which extends for more than a single pixel—so we aren't just cropping the screenshot of the window off-by-one-pixel, we have some larger difference here.
Comment 1 Radar WebKit Bug Importer 2023-09-25 16:00:29 PDT 
<rdar://problem/116020785>
Comment 2 Sam Sneddon [:gsnedders] 2023-11-02 10:06:56 PDT 
Created attachment 468459 [details]
Bad screenshot from the first example
Comment 3 Sam Sneddon [:gsnedders] 2023-11-02 10:07:08 PDT 
Created attachment 468460 [details]
Good screenshot from the first example