220197 2020-12-30 05:25:07 -0800 WKWebView inside a fullscreen quicklook preview lag while page scrolling 2021-01-11 10:51:49 -0800 1 1 1 Unclassified WebKit WebKit2 Safari 14 Mac (Intel) macOS 11 NEW InRadar P2 Normal --- 1 sbarex webkit-unassigned simon.fraser thorton webkit-bug-importer oldest_to_newest 1716834 0 sbarex 2020-12-30 05:25:07 -0800 I have a Quicklook appex that show the file contents by a WKWebView. The preview inside a normal quicklook window works well, but if the window is in fullscreen is not possibile to scroll with the trackpad gesture. I do not know is is related to bug [219632](https://bugs.webkit.org/show_bug.cgi?id=219632). Using the deprecated WebView insted of WKWebView the preview can be scrolled on fullscreen mode. I have created a demo code here: https://github.com/sbarex/QLTest 1717136 1 sbarex 2021-01-04 08:59:17 -0800 Also, non in full screen, if I click on a link to a local anchor, the scroll start after some delay. 1717364 2 webkit-bug-importer 2021-01-05 10:01:54 -0800 <rdar://problem/72817636> 1717366 3 simon.fraser 2021-01-05 10:02:15 -0800 The subject says "preview lag" but you also say "is not possibile to scroll". "Lag" implies that it scrolls, but slowly. Could you clarify? 1717638 4 sbarex 2021-01-06 06:30:06 -0800 In full screen mode, the two-finger gesture on the trackpad does not scroll the content. But executing the gesuture quickly (which in normal situation would make the content scroll fast) you can scroll about 2 lines at a time, jerky and without the elastic effect. 1718573 5 simon.fraser 2021-01-09 11:49:42 -0800 Please give instructions about how to use your test project to get fullscreen QuickLook. Should I run the QLTest target and choose "Open QuickLook for a test file"? What macOS version are you testing on? Does the bug only occur on some OS versions? 1718740 6 sbarex 2021-01-11 10:51:49 -0800 (In reply to Simon Fraser (smfr) from comment #5) > Please give instructions about how to use your test project to get > fullscreen QuickLook. Should I run the QLTest target and choose "Open > QuickLook for a test file"? > > What macOS version are you testing on? Does the bug only occur on some OS > versions? You must open the quicklook preview from the finder (open from the app do not show the fullscreen button!). Follow these steps: - download the precompiled test app from https://github.com/sbarex/QLTest/releases - move the app on the Applications folder (this force the detection of the ql extension) - launch the app and push on the button "browse for a test file" to select a test file on the finder. - From the selected file on Finder open the quicklook preview. - Maximize the preview to fullscreen. I'm using Big Sur 11.1 (Intel). On Catalina I do not detect this bug.