Sometimes scrolling the VE view causes this error to appear:
VM1039:formatted:13548 Uncaught TypeError: target.scrollTo is not a function at VeInitMwMobileFrontendArticleTarget.ve.init.mw.MobileFrontendArticleTarget.onWindowScroll (<anonymous>:421:678) at later (load.php?debug=false&lang=en&modules=ext.visualEditor.articleTarget%2Cbase%2Ccore%2Cdiffing%2Cmwcor…:1052)
Seems to be a side effect of 8b1208cb976278bd44025e6d2c86a3ea6ed8c177.