Mail.app signature preferences too big for screen Because I have so many .signature 'quotes' attached to Mail.app, when I switch to that tab in the Mail.app preferences, the window is too large for my screen.

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I cannot resize it with the top corners, and I can't reach the bottom corners to resize it.  Moom.app is installed on the Mac, but even that will not let me change the size.  I have tried to rotate the display by 90°, in the hope of being able to grab it that way.  I have also tried to modify the resolution of the display, but to no avail.
Any help appreciated.
Well, I deleted a lot of .signatures, but no luck.  I killed Moom, and that seems to have done the trick.  Curiously, I can't now replace my .signatures from Time Machine.  Ah, well.  Not to worry.  I never used most of them anyway.