I'm trying out 1.3.3 (and oh so very much looking forward to 1.4 for inline spellcheck) and sometimes I can and sometimes I cannot Cmd-A to Select All in the input pane. I'm experimenting at the moment, and I can't always get the combo right, but sometimes Select All (cmd-A) is grayed in the menu until I either use the cmd key for something else (such as cmd-arrows to move around) or select part of the input pane (with shift-arrows or selecting with the mouse). Then the selection becomes available and I can Select All as usual.
Sometimes, it becomes available when I select another application and return to Savitar.
I know this isn't terribly helpful, but until I can find an actual pattern, this is where I can see it.