Expand the file name input field in the single file editor
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## Proposal
Expand the file name input field in the single file editor - there is a lot of empty space on the right.
Currently, most filenames do not fit, and it's rather annoying to edit them when the input is so small.
The ideal scenario would be to make the input size dynamic and stretch it to the right when the window is resized.
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#### NOW

It's funny enough that it automatically expands when you make the window smaller, but that's not a solution.

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#### Ideal State

issue