If I do that, the lower window's button-tooltips won't work because its strata is lower than the upper window. Did you mean the opposite, maybe?
If I put Medium on the lower window, and Low on the upper window, it somewhat works better. Then the lower window's tooltips will override the upper one like it should, as you can see on the picture, if I would move the mouse up in the tooltip-field to Gu Cloudstrike #4 for example. I can also atleast move into the middle of the last bar 'Aktum' to get the tooltip show, which is an improvement afterall.
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Got some new suggestions btw.
# Give the real-time damage taken multiple keybind options, modifier+leftclick would be nice. An example: I would recommend ((ALT/CTRL/SHIFT+mouseLeftClick) or mouseRightClick). This is mostly because not everyone have a middlemousebutton. I, for instance have one but it's somewhat broken. I've also heard about people using middlemousebutton for Voicecoms.
# I noticed that in Auras & Voidzones, everything is shown, every little damage-hit. So it says often 0k dmg because it's so small. Or 1k, 5k.. nobody cares about such low dmg. Maybe have an option to choose Minimum % of HP that is recorded into Details. So this will work perfectly with the downscaling in WoD as well. Something like 0%, then everything is recorded, a slidebar up to 10%, something like that.
I added these into Spell Customization because I was tired of getting double spellnames. Otherwise it would be duplicated Atonement, Lifebloom & Power Word: Solace.
Lifebloom (bloom) means when lifebloom blooms, that part only is a whole new spell.
Atonement (Criticals) means, whenever your Holy Fire, Smite or Penance crits, they are counted into this spell.
Power Word: Solace (Criticals) means, when you use that talent, and when it crits it's counted into this spell.
So if you want to add these as default, that's up to you.