To reproduce:

• checkout project
• npm install
• npx cap build android --> it will use the build parameter provided in capacitor.config.ts

Result:

• it will build an unsigned apk, although the config is to build a signed apk.
• changing to jarsigner (in capacitor.config.ts) will build an signed apk. But due to the jarsigner is outdated, the app can not installed on Android 11 or higher.