TODO: Thickness anti-aliased lines cap are missing their AA fringe. We avoid using the ImVec2 math operators here to reduce cost to a minimum for debu

When using this function it is sane to ensure that float are perfectly rounded to integer values, to that e.g. (int)(max.x-min.x) in user's render pro

Note that shortcuts are currently provided for display only (future version will add flags to BeginMenu to process shortcuts)

delete the section

move cursor to first character of selection

We intentionally avoid using ImVec2 and its math operators here to reduce cost to a minimum for debug/non-inlined builds.

Use case A: Begin() called from constructor with items_height<0, then called again from Sync() in StepNo 1 Use case B: Begin() called from constructor

handle undo/redo thru this functions