Downloading .P8 file

Have you found a solution? I'm facing this problem right now and I need to fix this problem to can implement in app purchases

Me too.

Yes, this can happen depending on your browser settings. When you create a user API key in the Apple Developer Connect Store, the .p8 file is typically presented in the browser as a text file. This is normal behavior, and it allows you to view the contents of the key directly.

Steps to Save the .p8 File If the key opens in the browser instead of downloading, you can manually save it as a .p8 file:

Right-click on the Page:

If the key opens in the browser, right-click anywhere on the page. Select "Save As...":

Choose the "Save As..." option from the context menu. Save the File:

In the "Save As" dialog, make sure to select the file format as "All Files" (or "Text Document" if that's the only option). Enter a name for the file with a .p8 extension, like AuthKey_XXXXXXXXXX.p8. Choose a location to save the file and click "Save." This will save the key as a .p8 file on your local machine.