throttle the Pd window scrollbar to prevent layout thrashing
Throttle moving the scrollbar on the Pd Window to prevent expensive relayout of the DOM.
The delay was made small to preserve responsiveness, but it can be increased if necessary.
This should fix #219 (closed) and #381 (closed)
Unforuntately this doesn't help for the text window that opens with [text define]
. In that case, Pd will clear the window and send the entire contents to the GUI. This doesn't scale for text window contents greater than a few thousand lines.