[bug] can't preview image upload on safari

[BenGamma]

Describe the bug
On safari, when uploading an image, the preview doesn't show the image the user wants to upload.

To Reproduce
using safari, try to upload an image either in youe user /settings or in the create how-to page.

Expected behavior
User should be able to preview the image your are about to upload.

Screenshots
After image selected :

Additional context
Add any other context about the problem here.

[chrismclarke]

As a fix can I just give you a better web browser @BenGamma ? :p

I'm guessing this should also link with browser support (#611) and testing strategy.

[thisislawatts]

Unable to recreate in the latest version of Safari.