FEATURE: Show focused outline when editing text

[Sebobo]

Description

Currently no outline is shown when editing inline text when the mouse is not hovering the CKEditor field.

See also

Steps to Reproduce

1. Edit content and move mouse away

Expected behavior

Actual behavior

Affected Versions

Neos: 8.3
UI: 8.3

[Sebobo]

Possible solution something like this (with a different color of course):

.ck-focused {
    outline: 1px dashed red;
    outline-offset: 5px;
}