Hi,
I run Freecol 0.11.6 (Revision: ${Freecol.Revision} on linux Mint 20.04 and I get an error message (I got this error also on other version and on other OS but I just decided to report it today). Enemy town is on a tile (I can see the frontier around it) but the town is not shown on the tile. When I try to attack it (regardless witch kind of unit I try with)I get an error "server can not do that". I attached the log, a picture showing what I see and also the game save.
Thanks!
Thanks for the report, however this is probably a duplicate of BR#2982, which was fixed a while back. I loaded your game with the current trunk and the town (Williamsburg) was shown correctly, and I was able to successfully attack it. Consider running one of the
nightly releases for a more up to date version of FreeCol than 0.11.6.