[GNC] How to include images in the Wiki?

[Geoff]

Folks

After trying assist James Baxter to set up his Stocks, and mindful of 
his sage advice to "see if we can do better", I thought to enhance the 
"Stocks/add stock" section of the "Using GnuCash" Wiki with some 
screenshots to illustrate the process:-
https://wiki.gnucash.org/wiki/Stocks/add_stock

But I can't figure out how to upload an image that I can link to.

Does anyone know how to do this?  Or do I need to host images on a third 
party site?  If so, can anyone recommend one?

Thanks

Geoff
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