Disable Default "Highlight All" Expressions

How do I disable the default action of expression fields highlighting all the text when it's edited?   I just want to click ONCE and insert my cursor.  Right now I click, which wakes up the expression entry field and highlights all of the text, and then click AGAIN to insert the cursor to start typing.  

I have never ever ever ever ever ever wanted to click in the expressions field box and clear all of the text.  If I want to clear the expression I alt click the stopwatch.   And because no other text editor - Word, Gmail, Outlook etc - defaults to selecting all text, I can't tell you how many times muscle memory has had just start typing, but clearing out the original expression.

Thanks,

Marc