I’ve read they were Belgian Dessault Aviation practicing at Corsica👍
Suggest you read better sources then . Belgium never operated the Jaguar (or the Mirage 2000) and the three in the beat up are definatley Jaguars. Belgium did operate the Mirage V, but they were all dark green and brown. The only other European operators of the Jag were the RAF - but they were a different colour to these French ones. The only other European operator of Mirage 2000 is Greece. Corsica is possible though - never been there. Scrub that, just looked again on a better monitor. I think they are (well at least the first one is) Belgian Alpha Jets. If you single step through the frames you get one where you can see the tail more clearly - and you can see the tip is dayglow orange. Serials were in large white letters half way up the fin, and began "AT- , and you can see although not read that too.
Belgian Alpha jets operated from Brustem (in Belgium) and from Cazaux in France.
Dassault Aviation is a company similar to British Aerospace (BAe Systems) who make most of the fast jets operated by France. That includes the entire Mirage range, the Rafale and they were part of the consortium which built the Jaguar (SEPECAT) and Alpha Jet (Aerospatial and Dornier).