Card Cover image uploads but does not display

Question

I am editing a number of different cards, each on different topics.
I uploaded a graphic (jpeg) to one to serve as the cover.  It is displayed as expected.

On another card I uploaded a different graphic the same way:
I click > Cover
> Upload a Cover Image
Select the image (40KB jpg)

It uploads with no error but is displayed in the card thumbnail as a colored rectangle and does not appear at the top of the card.

When I double click on the colored thumbnail, it opens the correct image in a separate window  but it is not displayed in the card. 
(I can delete the image and display a pre-loaded Splash as the cover image but not this image or any alternative I have since tried)

John Hurley_6d0k51 · Answer

Are you serious?

Soumyadeep Mandal · Answer

Hi @John Hurley ,

Change your browser to google chrome!

John Hurley_6d0k51 · Answer

Hi Soumyadeep,
You may be right.  When I returned to the Card after a few hours, the cover was displaying correctly.
However, I have the same problem with other cards/covers and no other issues with my Internet.
I do get this error when I opt to open the cover graphic in a different tab:

But I have no issue reaching any other website.