I'd welcome if (color) sampling from alpha (ideally the background) would switch from paint mode to erase mode. Just as handy shortcut.. BTW I love also the idea to pick color from alpha, just erasing seems to me "more useful".
It must work like that either with a switch (turned off by default) and/or only when there is "Pick from current layer" mode is on.
(In reply to Tymond from comment #1) > It must work like that either with a switch (turned off by default) and/or > only when there is "Pick from current layer" mode is on. So what's the deal to tell Krita to switch to erase mode instead of paint mode, if we pick from alpha and no solid Pixel(s)? Imo, a nice shortcut instead to click some button on the top. Given the occasion..
All pixels have color, even the completely transparent ones (although they usually are just black). Especially with semi-transparent pixels we need to think how would it affect picking colors. yes, a nice shortcut - which means a separate 'action' from the implementation point of view - would be good as well.
Semi trasparent pixels shall be values very close to black, I guess a max of 10% brighter pixels to black is more than enough