Can't save Note document with en-gb browser language

My Chrome language settings are:
 
1. English (United Kingdom) - Google Chrome is displayed in this language
2. English
 
Create a new Note document with HTML format. Copy some text/image from a webpage and paste into Alloy editor (Note content). Click 'Save' button. See 'Note has been saved' toast popup message. Reload page, Note content is empty.
 
In dev tools Network tab, I see 404 for these urls:

/nuxeo/ui/bower_components/nuxeo-ui-elements/widgets/alloy/lang/alloy-editor/en-gb.js?t=H9MF
/nuxeo/ui/bower_components/nuxeo-ui-elements/widgets/alloy/config.js?t=H9MF
/nuxeo/ui/bower_components/nuxeo-ui-elements/widgets/alloy/skins/moono/editor.css?t=H9MF

 
(Note the en-gb.js)
 
Workaround:
Change order of languages in browser settings so that 'English' is at the top i.e.
1. English
2. English (United Kingdom) - Google Chrome is displayed in this language
 
Reload Note document page. See that url /nuxeo/ui/bower_components/nuxeo-ui-elements/widgets/alloy/lang/alloy-editor/en.js?t=H9MF is 200. Copy/paste webpage content again into Note content Alloy editor, page now saves ok.