Insert Object dialog box not translated in Welsh LibreOffice 5.0.2

l10n
#1

This may be an old issue that I've missed.
When you go LibreOffice>Writer>Insert>Object>Insert OLE Object...>Other

the resulting dialog box appears in English. The Object Type:

list appears be partly translated.
I've checked the 'Inserts a new Adobe Acrobat Document object into your document' string in Pootle but it's not there.
I'm running Windows 10 with the Welsh interface, in case it's something to do with Windows.
Thanks
Rhos