SUMMARY STEPS TO REPRODUCE 1. Select contiguous selection tool 2. Use [Alt] to use subtract 3. Don't move the mouse OBSERVED RESULT The minus symbol stays on the screen EXPECTED RESULT The minus symbol should be removed once the hotkey has stopped being pressed SOFTWARE/OS VERSIONS Windows: 7 Professional x64 ADDITIONAL INFORMATION If you move the mouse the minus sign will disappear, but if you just hit [Alt] it will stay there until you move the mouse. If you don't move the mouse and hit [Shift] it will stay as the minus sign and doesn't change to the plus sign. It's a tiny bug but it can be confusing as visually it looks like [Alt] is a toggling subtract.
*** This bug has been marked as a duplicate of bug 410532 ***