4827a3131e
The previous ElvUI-style border was too thick and uneven (thicker at the
top): it used Interface\ChatFrame\ChatFrameBackground with edgeSize = 1 UI
*unit*, which renders several physical pixels thick at the user's UI scale,
and a 1x1 texture that samples unevenly along edges.
Now copies ElvUI/Core/Toolkit.lua SetTemplate exactly: the blank texture
E.media.blankTex (Interface\Buttons\WHITE8X8) for bg + edge, and edgeSize =
E.mult (one physical pixel = (768 / screenHeight) / uiScale) so the border
is a true even 1px. Colors unchanged (ElvUI defaults the user runs):
backdropfadecolor {0.06,0.06,0.06} @ colorAlpha 0.8, bordercolor black.
Factored into QuestieTooltips:ApplyElvUISkin so the secondary learner frame
and the default tooltips share one implementation.