1470373 - session restored Google Calendar has missing icon font

Status: NEW

(Core :: Layout: Text and Fonts, defect, P3)

Description

[Cameron McCormack (:heycam)]

Attachment: screen shot

Recently, sometimes when I session restore a Google Calendar tab after restarting, it will be missing an icon font used on some of its buttons.

See the attachment for a screen shot.

Comment 1

[Chris Peterson [:cpeterson]]

I have occasionally seen this Google Calendar button bug, too. Perhaps it is related to missing Gmail button icon bug 1338652?

Comment 2

[Chris AtLee [:catlee]]

I hit this from time to time as well. Reloading the tab fixes the issue for me.

Comment 3

[Cameron McCormack (:heycam)]

This still happens to me, and again today this was after a browser restart / session restore. From the console:

> document.fonts.size
55
> [...document.fonts].filter(f => f.status == "error").map(f => f.family)
Array [ "\"Roboto\"", "\"Material Icons Extended\"" ]

Not sure if this is relevant, but I have two Google Calendar pinned tabs that get restored at roughly the same time. I don't think I've ever seen the icon font fail to load in both at once. Could there be some network / font loading race?

Comment 4

[Jonathan Kew [:jfkthame]]

That sounds worth looking into.... we have the user-font cache, which should mean that multiple pages (with the same origin) that use the same font resource end up sharing the same platform font rather than each separately downloading and instantiating it. However, in this case it's likely that at the time both your tabs want the font, it's not yet available in the cache because neither has downloaded it, so they both initiate downloads. Each of them will then presumably instantiate a platform font when its download completes, and try to put it into the user-font cache. Seems like there could be raciness/fragility of some kind there, resulting in one of the tabs sometimes failing.

OTOH, are your two Google Calendar tabs running in the same content process? If they're different processes, it's harder to see how an issue like this would happen, as they wouldn't be sharing any font caches. In a quick test of creating two pinned GCal tabs and restarting the browser, I got them in separate content processes - but presumably there's no guarantee of that.

Comment 5

[Cameron McCormack (:heycam)]

Oh, good point. They are in separate processes in my current browser session (which I think is still the same one as yesterday's).

Comment 6

[joshas]

Getting the same error on Fedora 32 on Wayland, Firefox 78.0.1 . Google Calendar is pinned as second tab, so I usually open it a bit later after browser starts. Sometimes logo goes missing too.

Comment 7

[joshas]

Attachment: google-calendar-missing-icons-and-logo.png