On a clean install of 7.1.5 when we try to edit a quote we get:
Uncaught TypeError: Cannot read property ‘appendChild’ of null line_items.js:135
Manually running the javascript creates the line. It seems that product_group0 does not exist when this is called.
I first downgraded item_items.js to 7.1.4 version and part of my problem was resolved. I have since merged 7.1.4 and 7.1.5 line_items.js keeping the new functions but restoring the old check from the new version of === and !== to == and !=.
Thanks for highlighting this issue, this issue has been logged (#117) and will be addressed in the next release