Paris during Easter

We were in Paris over Easter a few years ago. I don't recall anything being closed that wouldn't have been closed on any other Sunday or Monday. For historic reasons, France separates religion and government more than most other countries -- it's a proudly secular society. Many or all churches will have special services at Easter, but they will still be open to respectful visitors. Otherwise, I doubt if you'll find anything different about tourist attractions.

I remember that some restaurants were providing special Easter dinners, with advance reservations, the way they might at Christmas or New Year's. You might find your dining options constrained a little this way, but there will be plenty of other places to eat happily and well, believe me!

Paris sounds secular compared to Norway, my only foreign Påske holiday travel.
http://about-france.com/easter-in-paris.htm

Good Friday - the Friday before Easter - is not a public holiday in
France, so it's a day for business as usual in shops, museums and
restaurants – though perhaps a bit less busy than on a normal Friday,
since many Parisians take a long weekend and head off to the country
for this first holiday weekend of the year. The official holiday is on
Easter Monday which, in France as throughout Europe, is a public
holiday. Easter week is not necessarily a school holiday week; French
spring school holidays do not necessarily include the Easter week or
Easter weekend....

My contrasting Norwegian experience is Oslo starting to shut down the Wednesday afternoon before Easter Thursday, very limited and abbreviated lunch service on Easter Thursday and everyone seems to be in the mountains for Påske weekend including the Monday after Easter Sunday. Trains are heavily booked for the week ahead of Easter and holiday areas requiring multiday booking for the weekend.

Your question is a good one. What do French local do during holidays?

Easter Monday is a holiday in France,so all banks and post offices and government offices will be closed; public transport will be on a holiday (I.e. reduced) schedule. A few shops or restaurants may be closed that normally wouldn't be, but there are lots of restaurants closed on Mondays anyway, so you may not notice a difference.

Paris is not Norway.

I will be flying out of Paris on Easter Sunday this year and was planning on taking the RoissyBus to Cdg. Will there be any disruption of service?