Cannot find symbol class in Android Studio

It can happen if the library (be it a local module or external dependency) has a minifyEnabled true, but library's ProGuard configuration is missing or not correct (the class is eligible for removing by ProGuard). This leads to class not being compiled.

For me it was a similar problem but on proguard conf. proguard was active on a first library and inactive on a second.

Copie same proguard conf on all build.gradle has solved the "cannot find symbol class" error.