[BUG] Image toolbar moves outside of editor if image url is invalid

[jgeppert]

• I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• I have read the documentation and cannot find an answer.

Describe the bug
Image toolbar moves outside of the editor when image can't be loaded.
This is especially annoying if the editor covers the whole width of the page, because then most of the toolbar is not inside the window.

To Reproduce
Steps to reproduce the behavior:

1. Open an editor instance with image plugin
2. Insert image, use an invalid URL, e.g. /a.jpeg

Expected behavior
Image toolbar is fully contained within the editor.

Screenshots

Editor covering full width of the page:

Desktop (please complete the following information):

• OS: any
• Browser [e.g. Chrome, Safari]: Chrome

[jgeppert]

A naive solution could be to just add a min-width with roughly the size of the toolbar to the parent element. The only drawback i can think of is that this might not look right for very tiny images, but I'm not sure if that's a problem.