Ok, so here is how you do it...the easy-peasy fix.... it is more steps than the other two, but it works.
Ok go to your photo hosting site page and pull up the image you are wanting to use.
Now right click on the image itself to bring up the menu and at the bottom locate Properties.
Now here is the tricky part. You will need to focus on two different things:
At the top you should see the word General and directly under it is a string of numbers that ends in .jpg
Half way down you will see Address (URL) and it should start out with https://
Now look at both of these. The last half of the URL should be what is at the top, however these addresses can be overly long and get cut off...so what you need to do is at the top of the edit screen where you are posting the photo click the Img button
Then you copy the entire URL that shows and then simply type in the rest of that link as it shows at the top of that Properties screen.
Then simply click the Img button so the link as you type it should show: