long-running

long-running (comparative longer-running, superlative longest-running)

1. Operating for a relatively extended period of time.

   The long-running play finally closed on Broadway, just short of setting a record for longest playing.

   • 2019 December 18, Richard Clinnick, “Railway's 2020 vision”, in Rail, page 3:

     Services on SWR's neighbour Southern were badly disrupted for nearly 40 days in 2016-17 following a long-running dispute involving drivers union ASLEF and the RMT. And it's passengers - the very people the railway is there for - who are caught in the middle.