Ash-Shaykh Ahmad an-Najmee, rahimahullah, was asked the following question,
In our country the imams (usually) establish right after the salaah the recitation of some of the adhkaar in congregation of which falls under being a bidah. So, it compulsory upon the salafi brothers that they leave the masjid as (a) way to (show that we) criticize this action or do they remain up until they finish the prescribed dhikr in the legislated way?
If leaving the masjid will not necessitate any harm to them, then it is appropriate that they leave. And if it is going to necessitate harm to them, (then) they should (continue) sitting and keeping quiet (i.e. not participating with them), la hawla wa la quwwata illa billahi”