Posted January 04, 2024
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You have to convert the file from jpg to webp becouse all files in the gog folders are webp.
I did it and now it works.
Following steps:
a) Download the pic from the post above
b) change the file name to 5facf09e67b54bc9fed60013da4f433ad4a67aaa0b9963b0d5f90bf67cc7e7d4_glx_vertical_cover
c) Convert the file from jpg to webp; i used this website https://convertio.co/de/jpg-webp/
d) add the file to C:\ProgramData\GOG.com\Galaxy\webcache\46987898241894936\gog\1456460669
Now you have the picure.
Just renamed the file like ussnorway said but I don't know why but it only worked with the file-name from the post of ussnorway which nasdaqt quoted.