I made a new LibreOffice Calc document, but the XML Source button is greyed out, how can I get it to work?
(Ubuntu 17.10; LibreOffice 5.4.1.2)
In case it helps someone, even with 5.4.5.1 where the bug mentioned above is fixed, I found it still disabled… I found that this feature (and others) is disabled while Experimental Features are disabled. Go to Tool->Options->Advanced and check the Experimental Features checkbox. (this is also mentioned in the previous question Jim K links to above).
Experimental Features works amazing! I was able to import my XML data dictionary and create a spreadsheet of it instantly.
Love this feature! Really well done.
And there is more documentation here: Development/Calc/XMLSource - The Document Foundation Wiki