I love Aseprite and this is why want to it be the best.
I consider this a usability flaw: when you Shift+Click on several cels one by one Aseprite currently selects only those cels that were clicked, but not range of cels (as generally awaited for lists).
It is generally common for many software to add items one by one by Ctrl+Click, not Shift+Click. And also remove by Ctrl+Click again. And Shift+Click should select whole range of cels between last touched cel and cel you Shift+Click on.
Could it be fixed this general way?
Also: I understand that maybe cels Shift+Click tries to mimic Shift+Click behaviour of Marquee tool. But Shift+Alt+Click does not deselect here. And cels are generally list/table of elements, not bitmap. So it would be better to implement Ctrl+Click instead. At least we need a way to select range of cels by only two clicks.