"Server error or API not found." because dist/user.css is missing

[LudovicRousseau]

Detailed description of the problem

If I go to the "Settings" page I get a "Erreur: Server error or API not found." message in red

Steps to reproduce the issue

Install Lychee

Output of the diagnostics (Settings => Diagnostics)

Diagnostics
-----------
Warning: Dropbox import not working. No property for dropboxKey.
Error: Upgrade to PHP 7.1 or higher

System Information
------------------
Lychee Version (json):  3.2.12
DB Version:             update_030212
System:                 Linux
PHP Version:            7
MySQL Version:          50505
Imagick:                1
Imagick Active:         1
Imagick Version:        1687
GD Version:             2.2.4
Plugins:                

Browser and system

Firefox 65.0 on macOS Mojave

Debug

From Firefox logs I see that the file user.css is not found and get a 404 code from the server.
After I create this file using touch dist/user.css on the server I do not get the error any more.

I see that the file user.css should be created on upgrade by https://github.com/LycheeOrg/Lychee/blob/master/php/database/update_030208.php#L52
But in my case the directory dist/ is not own by www-data and the php script has no rights to create a new file there.

I propose to update the Diagnostics page to report that access rights for dist/ are not correct.
Or better, that the file user.css should be present and writeable by the web server.
Does Lychee really need a write access to the dist/ directory itself?

I also note that I can click on "Change CSS" in the Preferences. I get no error and even a "OK: CSS updated". But the file user.css has NOT been updated. Of course because the web server has no write access on this file.

[ildyria]

I propose to update the Diagnostics page to report that access rights for dist/ are not correct.
Or better, that the file user.css should be present and writeable by the web server.

👍

Does Lychee really need a write access to the dist/ directory itself?

Aside from the user.css not really.

[LudovicRousseau]

I made a proposal but I am not a PHP developer.
I was expecting someone would pick this task and implement what is missing it for me :-)