Tidy up MouseFilter

autoload/vimspector/internal/balloon.vim

@@ -171,15 +171,20 @@ function! vimspector#internal#balloon#CreateTooltip(is_hover, ...)
     augroup END
 
   else
-    " assume we are inside vim
     func! MouseFilter(winid, key)
+      if index(["\<leftmouse>", "\<2-leftmouse>"], a:key) < 0
+        return 0
+      endif
+
       let handled = 0
-      if index(["\<leftmouse>", "\<2-leftmouse>"], a:key) >= 0
       let mouse_coords = getmousepos()
+
       " close the popup if mouse is clicked outside the window
       if mouse_coords['winid'] != a:winid
         call vimspector#internal#balloon#Close()
-        else
+        return 0
+      endif
+
       " place the cursor according to the click
       call win_execute(a:winid, ":call cursor(".mouse_coords['line'].", ".mouse_coords['column'].")")
 
@@ -190,8 +195,7 @@ function! vimspector#internal#balloon#CreateTooltip(is_hover, ...)
         call py3eval("_vimspector_session.ExpandVariable(".line('.', a:winid).")")
         let handled = 1
       endif
-        endif
-      endif
+
       return handled
     endfunc