You can tell that the opinion is going to be a fairly lengthy one when the summary prepared by the staff of the Ninth Circuit is, as here, six pages long (and replete with innumerable bullet points).
Among other things, the opinion resolves whether legally admitted foreign citizens have a constitutional right to (1) possess guns, and (2) make political contributions in U.S. elections. (The defendant here was admitted on a tourist visa, but came to the United States pretty much weekly.) The Ninth Circuit says that, no, no such rights exist. They're civic and political rights. You can limit their exercise to citizens.
The case arises from a high-profile criminal prosecution in San Diego. Ravneet Singh made lots and lots of (illegal) political contributions to various San Diego officials in an attempt to ensure that city officials allowed him to develop the Chula Vista waterfront. There was an era in which San Diego was a hotbed of corruption and other official misconduct. The more things change, the more things stay the same.