Avoid lost selections with Shift pressed

When selecting Edges one by one by picking and by keeping Shift pressed I would expect that my selection can not get lost. However, when my next pick by accident goes outside the Selection-Radius  for Edges (just a little more towards the Face-Center), I lose my existing Edge Selection, everything gets deselected. That's not at all what I want. One can easily try this out with a Grid with a couple of Edges selected.
I would always want to add to an existing Selection with Shift and I would always want to subtract from an existing selection with Ctrl. Is this doable?

in edit> customize> tools> Common modeling tools.

set shift to include selection instead of it;s defualt of toggle selection.

Hmm, I did as you told but I don't see any change.
Clicking away from Edges still deselects.

from my experience while holding shift the olny thing that will clear the selection is clicking the viewport BG

from my experience while holding shift the olny thing that will clear the selection is clicking the viewport BG

Not here. I lose selections also when hovering over an object and clicking away from Edges. I also wouldn't want to lose my selection when accidently clicking the Viewport-Background while holding Shift.

ya as long as include selection key is held down, it should be impossible to lose it, or that is what would make the most sense.

so hopefully that gets changed at some-point, even know i never really ran into that problem.

have you tried setting a larger selection radius in the preferences window? That should allow you to be quicker and a bit sloppier with selections and still have it grab something.

i use a pretty high radius of 24 and dont have issues with selection.

Another good hint