I've seen this one in my log before when using text-selection on pages. You can reproduce this by long-tap holding in content on about:logo.
Hm, this is an error we're catching ourselves, so it shouldn't lead to other failures, but I can look into why this is happening. Also, I just noticed that we don't properly clean up after ourselves if we bail in startSelection. We should fix that.
Created attachment 649712 [details] [diff] [review] patch Logging this error is pretty useless, but we should make sure we clean up after ourselves if we're bailing in startSelection. This patch takes care of that.
Comment on attachment 649712 [details] [diff] [review] patch [Approval Request Comment] Bug caused by (feature/regressing bug #): bug 695173 (text selection) User impact if declined: logging a useless error isn't really a big deal, but without cleaning up properly, we can fail to remove the pagehide listener, which may cause issues Testing completed (on m-c, etc.): landed on m-c 8/8 Risk to taking this patch (and alternatives if risky): low-risk, adds code to clean up state of SelectionHandler when we fail to start a selection String or UUID changes made by this patch: n/a
Comment on attachment 649712 [details] [diff] [review] patch Small patch, low risk, wouldn't normally be a candidate for uplift but it's good to clean up the unused errors so approving for branches.