this is FUD. Inventing another candidate while already sitting on already existing lists of tons of Navalny supporters? supporters to whom nothing happened through all that time? doesn't pass the smell check
Navalnyists are soft-banned in Russia. They can't make any meaningful public statements without hitting one of the censure laws (e.g. it's illegal to say anything about the war that differs from the official Kremlin line). The FSB just slaps the "foreign agent" designation onto the more loud ones and makes their lives difficult enough for them to migrate away. It's a slow cleanse but it's pretty effective.
I replied to comment claiming a candidate was invented by our gov to collect PII of people who signed for him. Until people who donated/signed for Navalny are in trouble I don't see why that can be true
There are tons of Navalny non-supporters who are latently opposed. Personally I'd say that they are actually more dangerous to the regime due to the stratum they represent. You just don't hear it on the internet because they are older and have shit to lose. Alexey was a youth's idol, not adults'. Many people never considered him a good politician, if mediocre. Maybe that other person wasn't "invented", but they definitely could use him as a trap. There's no way anything could change here through "elections".