I did a signed release build in Construct and ran the following command on it:
.\apksigner.bat verify --verbose .\test-signed.apk
It produced the following output:
> Verified using v1 scheme (JAR signing): true
> Verified using v2 scheme (APK Signature Scheme v2): true
> Verified using v3 scheme (APK Signature Scheme v3): false
> Verified using v4 scheme (APK Signature Scheme v4): false
> Verified for SourceStamp: false
> Number of signers: 1
The line "Verified using v2 scheme (APK Signature Scheme v2): true" appears to indicate the APK is already signed with the APK Signature Scheme v2.
So I don't know why the Play Store would show an error. Perhaps if you are using your own key it is that key which does not support the v2 scheme? It seems to be valid if you use Construct to both create the key and sign with it. The build server uses apksigner, which is the official Android build tool for signing APKs, and according to the documentation, it appears to automatically detect the signing schemes to use, and according to my test it appears to indeed be correctly adding the v2 scheme. Maybe you could run a similar apksigner command to identify the schemes being added to your own APKs.
If I speculate, perhaps the v2 scheme can only be added if you use the same password for the keystore and the key - after all, the official keytool program no longer supports different passwords (hence the headache about having separate passwords last year), so maybe the v2 scheme doesn't support different passwords either. 🤷♂️
Android APK Signing Tool (APK Signer)
Here you go, this is the application that many people used to sign applications with.
Now the key that was created with it must be used in the Construct 3 system.
And signing the application in Construct 3 using the old key (what was created at the beginning outside of Construct 3) which is associated with the Google Play market gives an error.
Is it possible to somehow expand the signing functionality in order to experiment with the activation checkboxes with v1 v2 v3 and so on?
I understand that you can talk about this forever, but how exactly to solve this issue.
Study the ANDROID SDK? Well, you can, well, you have to study)))