Gallery: uploaded image not available in Edit view

[eliorivero]

Context

While authoring a post, I added an image gallery. Shortly afterwards, I wanted to add one more image to the gallery and rearrange the items.

Expectations

Since Edit is available after uploading an image, I hoped to be able to rearrange the items as soon as the image was uploading–or at least after it was uploaded–without having to save and reload the page.

Reality

Right after adding a gallery block and adding the images, I realized there was another one I wanted to add. I clicked the button Upload an image and uploaded it.
Since it was instantly visible in the editor, I wanted to re-arrange the thumbnails, so I clicked the pencil to edit the gallery. To my surprise, the image wasn't there.
I waited briefly until it was uploaded and tried one more time. Again, the image wasn't there.
I saved, reloaded, and this time the image was shown in the gallery edit mode.

[youknowriad]

Seems like a duplicate of #9073