Bug 207123

Summary:	CSS Filter: drop-shadow() disappears when element is hidden by overflow
Product:	WebKit	Reporter:	chototoro <b.houdusse>
Component:	CSS	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	ahmad.saleem792, b.houdusse, sabouhallawa, simon.fraser, webkit-bug-importer, zalan
Priority:	P2	Keywords:	BrowserCompat, InRadar
Version:	Safari 13
Hardware:	Mac
OS:	macOS 10.15

Description chototoro 2020-02-03 09:01:29 PST

When a drop-shadow() filter is applied to the child of an element with hidden overflow, the filter will only appear if at least 1px of the child element is still visible.
A test case is available here: https://codepen.io/chototoro/pen/Jjogeyd

Bug appears on Safari (12.1 and above), on macOS and iOS.
Behavior is normal on Chrome, Firefox, and Edge 79.

Comment 1 Radar WebKit Bug Importer 2020-02-04 00:10:08 PST

<rdar://problem/59141775>

Comment 2 Ahmad Saleem 2022-10-01 16:30:43 PDT

I am still able to reproduce this bug in Safari 16 / STP 154 using CodePen from Comment 0 and it does not show "pixels" in case of "No pixel visible" (fourth - bottom right square / box) and it does not show anything in case of Safari while both Chrome Canary 108 and Firefox Nightly 107 does match each other in all four cases and three cases with Safari except the one mentioned above. Thanks!