See editing/selection/5195166-1.html This boolean needs to be cleared when opening a new document, when programatically changing the selection. Also programattic modify()s should probably be treated as userTriggered selection operations, since they exist primarily to test user triggered operations.
Justin added this FIXME via this commit: https://github.com/WebKit/WebKit/commit/94dbb6b9a2e1b1803adc4fbd7c5ff7c787e78920 but now in the latest test case does not have this: https://github.com/WebKit/WebKit/blob/11adcf008ef8a0287a435298802c45749dd17cc1/LayoutTests/editing/selection/5195166-1.html#L4 Do we need to do anything more here? Thanks!
Yeah, https://commits.webkit.org/47861@main removed this code.