Intellij modules not finding generated protobuf classes in a multimodule maven project (but works fine via maven cli)

I have a project set up like this:

protos/           # protobuf files here
pom.xml           # parent pom
services/common   # this module generates the protobuf classes
services/mod-1    # imports common, but in intellij only protobuf classes not found
services/mod-2    # imports common, but in intellij only protobuf classes not found

My protobuf generator looks like this in services/common/pom.xl

            <plugin>
                <groupId>io.github.ascopes</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>3.4.1</version>
                <configuration>
                    <protocVersion>4.31.1</protocVersion>
<!--                    <protocArtifact>com.google.protobuf:protoc:4.31.1:exe:${os.detected.classifier}</protocArtifact>-->
<!--                    <outputDirectory>${project.build.directory}/generated-sources/protobuf/java</outputDirectory>-->
                    <sourceDirectories>
                        <sourceDirectory>${project.basedir}/../../protos</sourceDirectory>
                    </sourceDirectories>
                    <registerAsCompilationRoot>true</registerAsCompilationRoot>

                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

Now when I run mvn compile, all the modules resolve the protobuf classes and everything compiles correctly.

But in intellij, mod-1 and mod-2 cannot resolve the protobuf classes.

What am I doing wrong?

You need to tell IntelliJ to generate those classes, otherwise it won't be aware of them, even if their creation is part of the default maven lifecycle.

Right-click on the project's folder or the pom.xml, then Maven > Generate Sources and Update Folders.