‘Add Point’ Hangs

I'm using the latest WordPress and I can no longer 'add point', the grey spinner just spins. I get the following js error. 

Uncaught TypeError: e is undefined
uh https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
uh https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
focus https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
execCommand https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
execCommand https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
execCommand https://www.mysite.comwp-includes/js/tinymce/tinymce.min.js?ver=49110-20201110:2
success https://www.mysite.comwp-content/plugins/devvn-image-hotspot/admin/js/maps_points.js?ver=1.2.2:158
jQuery 4
nrWrapper https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
inPlace https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
XMLHttpRequest https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
nrWrapper https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
nrWrapper https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
XMLHttpRequest https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
jQuery 5
https://www.mysite.comwp-content/plugins/devvn-image-hotspot/admin/js/maps_points.js?ver=1.2.2:104
jQuery 2
nrWrapper https://www.mysite.comwp-admin/post.php?post=1257&action=edit:6
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