In May 1946, French voters went to vote on a proposed constitution. Backed by the left, it would've given the 4th Republic a unicameral parliament. The right claimed that the constitution would've turned France into a communist state and the scare tactics worked with 52.8% voting against it. In October 1946, a different constitution, which incorporated a senate, was passed and lasted another 12 years before a military coup brought Charles De Gaulle to the Presidency and brought the 5th republic to fruition.
So what if the other constitution had passed? Would France be more stable in the 50s as opposed to the dozens of prime ministers we got IOTL?