I would suggest to read the actual paper Russia-Trump inquiry: Full text of Mueller's indictment. And not what commentators say about it.
Squarely focused on the Russian active measures. What's notable is that it's not just a "Russians on a Pro-Trump disinformation campaign" thing, the objective seems to be to sow distrust among Americans. Of course, that's an easy field to plow.
And note that it didn't end after the election, just on spec:
57. After the election of Donald Trump in or around November 2016, Defendants and their co-conspirators used false U.S. personas to organize and coordinate U.S. political rallies in support of then president-elect Trump, while simultaneously using other false U.S. personas to organize and coordinate U.S. political rallies protesting the results of the 2016 presidential election. For example, in or around November 2016, Defendants and their co-conspirators organized a rally in New York through one ORGANIZATION-controlled group designed to "show your support for President-Elect Donald Trump" held on or about November 12, 2016. At the same time, Defendants and their co-conspirators, though another ORGANIZATION-controlled group, organized a rally in New York called "Trump is NOT my President" held on or about November 12, 2016. Similarly, Defendants and their co-conspirators organized a rally entitled "Charlotte Against Trump" in Charlotte, North Carolina, held on or about November 19, 2016.