...who recently got 19 years on extremism charges. on top of what he's currently serving for embezzlement.

The western take is that its all made up: "..a politically motivated strategy by the Kremlin to silence its fiercest critic." as ABC put it
...but of course you don't get any evidence reported in Western media so its hard to make up your mind if there is anything in the charges... is perhaps the Russian state over-reacting by using a sledgehammer to crack someone who appears to be merely a Juan Guaido type Western tool?

-Penny for the thoughts of those who have studied this a bit more than my mere cursory glance.