yes, the docker run is a one-way street and will rudely “repo sync” your changes away. I guess the easiest is to build the docker image yourself, inheriting it with a FROM and replacing just the script build-community.sh script (target is build.sh if I remember correctly, check first) and outcomment the sync therein. Importing and then use COPY build-custom.sh build.sh similar to what is described at Modifying a prebuilt Docker image - #2 by tcecyk …
I abandoned the docker method myself, it’s too sequential if you modify/debug and I’d be giving up on make comfort. But it’s damn easy I admit.
For a prebuilt it’s sufficient to just have the Android.mk beside the apk and name it in either PRODUCT_PACKAGES. For the build-community.sh script, theres a variable you can use - CUSTOM_APPS, see How to Build the /e/OS ROM?
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