1572498 - some buttons (e.g., Check for Updates / Restart Nightly) in Firefox UI don't update until the mouse hovers over them

Status: RESOLVED WORKSFORME

(Core :: Layout: Form Controls, defect)

Description

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

So this is something that I've been noticing for at least a month on Windows, but I've never seen it on Linux. It's not particularly clear to me what layer the bug is in; at first glance it looks like the sort of thing that might be a graphics bug, but I suspect it may well be at a substantially higher layer.

Basically, when I go to the "About Firefox" dialog to check for updates, there's UI that changes from "Downloading update" to "Applying update" to a button that says "Restart to Update Nightly".

On Linux, and in the past on Windows, the change from "Applying update" to "Restart to update nightly" happens at basically the same time that the update available icon shows up in the hamburger menu at the right edge of the toolbar in the Firefox browser window.

However, the bug is that the button doesn't actually appear visually until I move the mouse over it; in other words, the UI doesn't update until I hover over the button.

A video of this problem is here: https://photos.app.goo.gl/FG4nKTe6EPm3pnUV8

I see this basically every time on Windows; I don't see it at all on Linux.

Steps to reproduce:

1. start a nightly for which there will be an available update but it hasn't downloaded yet
2. Go to Help -> About Firefox
3. wait for the update to download

Expected results: "Applying update..." text turns into "Restart to update Nightly" button when the update is ready (which is the same time the updates icon appears in the hamburger menu).

Actual results: "Applying update..." text turns into "Restart to update Nightly" button when I move the mouse pointer over the text.

(I think I've also seen basically the same thing in about:crashes when submitting crash reports -- and in that case the thing that didn't happen until I hovered the button wasn't just "Submit" turning into "View" but the report moving from the unsubmitted to the submitted section of the page. I've only seen that once, so I'm not 100% sure it wasn't just coincidence that it happened exactly when I hovered over the button.)

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:jfkthame, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 2

[Jonathan Kew [:jfkthame]]

I just tried a couple of times to reproduce this with Nightly on my Windows machine, but it didn't happen for me. David, are you still seeing this consistently?

Comment 3

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

I'm not -- I think it probably went away about a week ago?