The Salaf would not attend even the funerals of the innovators, let alone sit with them on public stages and praise them to their faces.
They would not mix with them in life, nor honour them after death. Shaikh Zayd bin Muhammad bin Haadee al-Madkhalee (hafidhahullaah) stated:
“When Bishr al-Mareesee died, not a single Sunni attended his janaazah – and this was alongside the fact that that the people of Sunnah were widespread in the land – except one man from Ahlus-Sunnah did attend, and he knew what Bishr al-Mareesee was upon from “Tajahhum”, i.e. negation of the Names and Attributes, denial of the punishment of the grave, denial of the intercession on the Day of Resurrection – however he only attended the funeral to make du’aa against him, not to make du’aa for him! So when Bishr was placed in his grave, this Sunni supplicated:
“O Allaah! If this servant of your’s denied the Punishment of the Grave, then let him taste the Punishment of the Grave the likes of which no one from existence has ever tasted!”
So when the people supplicated, he likewise continued to supplicate:
“O Allaah! If this servant of your denied the Intercession of the Day of Resurrection, then do not permit any of your servants to intercede for him.”
When he returned to his companions from Ahlus-Sunnah, they said to him, “You claim you are a person of Sunnah, yet you accompanied the funeral of Bishr?!” He responded, “Don’t be hasty until I inform you [of what I did].”
So he informed them regarding what he had done and said – they believed him and laughed after initially being annoyed and angry with him.” 
So the origin with ahlus-Sunnah wal-Jamaa’ah, the Salafis, is that they do not attend the gatherings of ahlul-Bid’ah, they do not praise them or honour them, or share platforms with them – and even if an Imaam of the Sunnah agrees to attend, then it is for the purpose of clarifying the truth and exposing their misguidance, as Shaikh al-Albaanee and others have stated, and this is the way of Shaikh Rabee’. So the Salaf were clear with regard to the ijmaa’ concerning disassociation from ahlul-Bid’ah.
Any claimant to knowledge who attends the conferences of ahlul-bid’ah and shares platforms with them, being openly cordial with them, without correcting them and forbidding their innovations, then such a person has opposed the methodology of the noble Salaf and had contradicted the Salafi manhaj. He has given the impression to the masses that he is pleased with their innovations and their hizbiyyah.
The Messenger (sallallaahu alaihi wasallam) also warned against the People of Innovation, from befriending, supporting or taking from them:
“Whoever innovates or accommodates an innovator then upon him is the curse of Allaah, His Angels and the whole of mankind.” Reported by Bukhaaree (12/41) and Muslim (9/140)
The consensus of the abandonment of the people of innovation has been reported from a group of the Salaf – and whoever denies or rejects this ijmaa’ is either ignorant or himself a person of innovation. Al-Fudayl bin ‘Iyaad (d. 187H) said:
“I met the best of people, all of them people of the Sunnah and they used to forbid from accompanying the people of innovation.” Reported by al-Laalikaa’ee (no.267)
 See: Taareekh Baghdaad of al-Khateeb (7/22), Akhbaar adh-Dhiraaf wal-Mutamaajineen of Ibnul-Jawzee (p.70), from the book: at-Ta’leeq al-Mateen ‘ala Asl as-Sunnah wa I’tiqaad ad-Deen of the two Imaams ar-Raaziyain by al-’Allaamah Zaid bin Muhammad bin Haadeeal-Madkhalee, (p. 196)