Bug 1966586 - Reuse other browser windows when opening _blank links in Taskbar Tabs windows. r=nrishel
This doesn't affect other tab additions, nor does it stop the tab bar
from appearing altogether. The idea is that _if_ another tab is somehow
made, the user should see it; but we should not create new tabs if we
can avoid it.
This also adds tests for opening URIs in popups and taskbar tabs to make
it less likely that this breaks in future.
Differential Revision: https://phabricator.services.mozilla.com/D253726
<!DOCTYPE html><metacharset="utf-8"><title>CSS Values and Units Test: support for the ch unit</title><linkrel="author"title="Jason Leo"href="mailto:cgqaq@chromium.org"><linkrel="help"href="https://drafts.csswg.org/css-values-4/#ch"><linkrel="match"href="reference/ch-unit-019-ref.html"><metaname="assert"content="The ch unit should fallback to 0.5em or 1em respectively when it's impossible to derive the width of the “0” (ZERO, U+0030) glyph in the font used to render it"><style>@font-face{font-family:"icon-font";src:url("data:font/woff2;base64,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")format("woff2");}div{height:10px;background-color:blue;margin-top:10px;}div::before{content:"\e00b";display:none;}.test{/* 50px + 10 * (0.5em)*//* 50px + 10 * (0.5 * 10px) = 100px*/width:calc(50px+10ch);}.test-upright{writing-mode:vertical-rl;text-orientation:upright;/* 50px + 5 * (1em)*//* 50px + 5 * (1 * 10px) = 100px*/width:calc(50px+5ch);}.ref{width:100px;}</style><p>The test passes if there are two blue rectangles of equal length.</p><!-- In the cases where it is impossible or impractical to determine the measure of the “0” glyph, it must be assumed to be 0.5em wide by 1em tall. Thus, the ch unit falls back to 0.5em in the general case--><divclass="test"style="font: 10px icon-font"></div><!-- and to 1em when it would be typeset upright (i.e. writing-mode is vertical-rl or vertical-lr and text-orientation is upright).--><divclass="test-upright"style="font: 10px icon-font"></div><divclass="ref"></div>