1269392 - browser_1007336_lwthemes_in_customize_mode.js intermittently fails when lwthemes menu isn't populated before popupshown event

Status: NEW

(Firefox :: Toolbars and Customization, defect)

Description

[Jared Wein [:jaws] (please needinfo? me)]

From the test,

>   let popupShownPromise = popupShown(popup);
>   EventUtils.synthesizeMouseAtCenter(themesButton, {});
>   info("Clicked on themes button");
>   yield popupShownPromise;
> 
>   let header = document.getElementById("customization-lwtheme-menu-header");
>   let recommendedHeader = document.getElementById("customization-lwtheme-menu-recommended");
> 
>   is(header.nextSibling.nextSibling, recommendedHeader,
>      "There should only be one theme (default) in the 'My Themes' section by default");

The code under test uses onpopupshowing to populate the menu, but the onpopupshowing code calls AddonManager.getAddonByID to get the default theme as well as the suggested themes. This call is async and may not complete before onpopupshowing has returned.

I am able to reproduce this test failure locally (though intermittently) on my Linux Mint VM.