After moving to another Server Gallery can't display thumbs

After transferring my site to another server I have problems with the gallery. Neither in the manager nor in the frontend thumbnails or images are displayed.
What have I tried so far?
Reinstallation of Gallery → no success
Check these settings:
gallery.core_path → not found in the system settings
gallery.assets_path → not found in the system settings
gallery.files_path → [[++assets_path]]gallery/
gallery.assets_url → not found in the system settings
gallery.files_url → [[++assets_url]]gallery/

The link to the thumbnails looks like this: /assets/components/gallery/connector.php?action=web/phpthumb&ctx=web&w=730&h=500&zc=0&far=&q=90&src=https%3A%2F%2Ffmbc-vienna.at%2Fassets%2Fgallery%2F24%2F753.jpg

src interpreted as: https://fmbc-vienna.at/assets/gallery/24/753.jpg shows the image correctly.

MODX: 2.8.7-pl
Gallery: 2.0.2-pl
PHP: 8.2.24

Any help is highly appreciated!

Mike

So when you request the URL /assets/components/gallery/connector.php?action=web/phpthumb&ctx=web&w=730&h=500&zc=0&far=&q=90&src=... .jpg in the browser, what is the response? What is the HTTP response status code?
Do any errors get added to the MODX error log?
Do the other thumbnails in MODX (for example in a media source) work correctly?

No, the page remains blank

304

Thanks for asking. When I wrote the first post there was nothing in the log even after setting $config_disable_debug = false; but now there is something I mean important:

[37] => ImageMagickThumbnailToGD() failed in file "phpthumb.class.php" on line 3989
All attempts to create GD image source failed.
ImageMagick failed with message (sh: : command not found)
ImageMagick is not installed (it is highly recommended that you install it).
Source image is too large (1300x1390 = 1.8Mpx, max=0.0Mpx) for GD creation (either install ImageMagick or increase PHP memory_limit to at least 15M). in file "phpthumb.class.php" on line 4351
    [39] => phpThumb() v1.7.22-202312071641

But according to php.ini ImageMagick is available:
Additional .ini files parsed /etc/php82-fpm.d/ext/imagick.ini, /etc/php82-fpm.d/ext/opcache.ini

imagick module version	3.7.0
imagick classes	Imagick, ImagickDraw, ImagickPixel, ImagickPixelIterator, ImagickKernel
Imagick compiled with ImageMagick version	ImageMagick 6.9.12-80 Q16 x86_64 17733 https://legacy.imagemagick.org
Imagick using ImageMagick library version	ImageMagick 6.9.12-93 Q16 x86_64 17898 https://legacy.imagemagick.org

Yes they do.

This is a weird response code. 304 means “Not Modified”.

In the code, this response code should only be returned, if the request header If-Modified-Since is sent with the request, and the requested resource hasn’t changed (since the time sent in the header).