1422619 - Device preview shows empty page

Status: RESOLVED DUPLICATE of bug 1407830

(DevTools :: Responsive Design Mode, defect, P1)

Description

[Yves Goergen]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171112125346

Steps to reproduce:

* Open any website in Firefox for Windows (desktop)
* Enable device preview (Ctrl+Shift+M)


Actual results:

Sometimes, the page is displayed in the smaller viewport. Sometimes a blank page is displayed. Reloading doesn't fix it. To fix it, close the tab and then retry in a new tab. Sometimes the blank page remains blank when leaving that device preview mode. So the entire tab is effectively broken and will not load anything anymore. Never.

Comment 1

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

Thanks for filing!  I agree that's quite frustrating!

We made some improvements on this front in Firefox 58, but it's possible there's still more to do.

What version of Firefox where you testing here?  If it's earlier than 58, could you try Nightly (now 59)?

Comment 2

[Yves Goergen]

I am using the latest stable, now 57. I could test nightly, but the bug is not reproducible. I don't know what site I had the problem with so I can't verify there's any difference in nightly.

Comment 3

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

Okay!  In the past, I've usually triggered the issue by toggling RDM open and closed from the keyboard (Ctrl-Shift-M on Windows), and eventually it would break like you describe within ~20 attempts if it was going to happen at all.

It shouldn't really depend to much on the page being viewed.

Let's assume it's fixed by 58 and above for now.  If you discover that it's not, please reopen this bug.