Does not save edited Libraries to the original name

[TLK2A]

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Describe the bug When editiing a custom library (the collection of icons) and saving it, I am asked to specify a location. If I decide to overwrite the original file and accept the warning, then a endless circle "Wird gespeichert." (circular progress bar without progress) is displayed. Strange enough I can press "cancle" which closes the libraries window and omits all changes, but the circle remains.

To Reproduce Steps to reproduce the behavior:

1. Open draw.io-windows-no-installer (Version 20.3.0), create a New Library, place some icons and save it.
2. Close draw.io
3. Open draw.io-windows-no-installer (Version 20.3.0) (existing drawing or new drawing makes no difference)
4. Click on the pencil of the Library you created to edit it.
5. A popup window appears in the centre of the screen allowing to edit the Filename (on top) the icons below and offering "cancel", "export", "import", "add images", "save" (save is blue)
6. Delete icons by clicking on the black cross-button displayed in their upper right corner
7. Click on "save"
8. The circular progress bar appears and is overlayed by a explorer window titled "save as" that points to the directory where the library is present as file and has the filename filled.
9. Press the "save" button on that window without changing anything
10. A windows warning appears telleing that the file already exists and if I want to overwrite it. (button "ok" and "cancle")
11. press "ok"
12. Now you see the circular progress bar for ever above the window from step 5 (the 5 buttons of the window are clickable. "cancle" removes the window and resets the library to its original state. The progres bar remains)

Expected behavior In step 12 I expect that the progress bar stops as soon, as the file is written (in seconds) and the window is closed. The Library reflects the changes I made.

Screenshots If applicable, add screenshots to help explain your problem.

draw.io version (In the Help->About menu of the draw.io editor):

• diagrams.net 20.3.0

Desktop (please complete the following information):

• OS: Windows 10 Enterprise 20H2 (no administratve permissions)

Additional context Add any other context about the problem here.