bug#39342: Incompatibility between font-latex-fontify-script and mouse dragging a selection.

[Konrad Podczeck]

Accept the default setting of font-latex-fontify-script.

Set scroll-conservatively to 101.

Now make a selection by dragging the mouse. Extending the selection by dragging 
the mouse below the status line (or under the bottom of the frame) makes the 
cursor position, and thus one end of the region, to dance between the bottom 
and the middle of the window. The problem goes away if one sets 
font-latex-fontify-script to nil.

Konrad