Hi all,
An interesting bug?? popped up recently that we haven't noticed before.
(file created on local machine)
If a powerpoint file is created with some default information added to the slides and then going into the info pane and editing the 'Title' in the properties area to 'My New Title' (just a random test title)

Now, the document is saved as normal and closed. you can also verify that the title has changed from within windows explorer:

then we proceed to upload to a document library on sharepoint.
[for test purposes i created a blank default document library, no changes bar adding the 'Title' and 'Version' column to the view and removed 'Modified By']

ok, all looks good. So i go to edit the presentation in the browser using powerpoint online. nothing fancy, only adding in a new slide and some text. saving is automatic.
Then i return to the Document Library and the 'Title' of the document has updated itself!

Note, 'Example' in the title column in the picture above is the text from the first slide of the pptx.
I have repeated the above steps, but i edited with powerpoint on my machine and the 'Title' will remain unchanged.
My questions are:
Why does it affect powerpoint online only?
Is there a way to stop this, as I'd like to retain the title that i add per document.
any help would be greatly appreciated.
Regards
Will