Cracking the fingers during prayer

Shu'bah, the freed slave of Ibn Abbas (may Allah be pleased with them both), said: I prayed alongside Sayyiduna Ibn Abbas (may Allah be pleased with them both), and during the prayer I cracked my fingers. When I had completed the prayer, he rebuked me and said: You crack your fingers in prayer?

Ibrahim considered it disliked to crack the fingers in prayer.

Ata considered it disliked to crack the fingers in prayer.

Sa'id bin Jubayr said: Five things make the prayer deficient: stretching, looking here and there, turning the pebbles over, (giving way to) stray whispers, and cracking the fingers.

Ibrahim and Mujahid considered it disliked to crack the fingers in prayer.

It is reported through Layth from Mujahid that they both (Ibrahim and Mujahid) disliked a man cracking his fingers while he is in prayer.