Was this always like that ? It happens for * any * script, even a script that just does print "hello world" ?
#MenuTitle: Set Transform Origin to Centre of Selection
# -*- coding: utf-8 -*-
__doc__="""
Sets origin point for Rotate tool to the centre of the selection.
"""
print "hello world"
macOs 10.12.6 (16G1114)
Version 2.5.1 (1140)
Happens in starting GA in Shift+Alt safe mode too?
Close. Earlier on, it would load the base libraries at startup and startup would take longer.
Rainer is right. I can fix it but that will break a lot scripts. I see what I can do.
Have been pondering this same glitch lately, knew that it was a new thing, but didn’t understand why.
How much longer of a startup time are we talking for auto loading base libraries? I don’t see app startup time at a critical length of time, yet I did spend many years working in 3d Studio Max, which had uncanny load times. 
We found a little glitch today which caused Glyphs to load more libraries than necessary for the script in question. Next version will be a little snappier. D
@oneweioranother also said: It happens for any script This is also my experience, regularly when using Delete All Anchors from @mekkablue’s GitHub as well as others not coming to mind at the moment.
You mean, not only the first time you run it?
I took this as you fixed it for a specific instance of the lag/beach ball, not an overall fix. Anywho, sounds like there’s been progress made. Will wait patiently for the next version.