I bought Into the Breach on Galaxy of Gaming for linux on release. In July 2022, Subset games released Into the Breach Advanced Edition, (1) a free expansion of the original. This article details how I upgraded and moved my save game files across to the latest version of the game.
Game save data is stored in files with the names in the foramt: profile_{Name}. (2)
The first version I installed was GOG v1.0.10 (2-28-2018). This version was run via wine (3), and installed to ~/.wine/dosdevices/c:/GOG Games/Into the Breach/. The save game files (eg. profile_Alpha) were saved in the top level of this directory.
I installed the latest version of Into the Breach from GOG as of Feb 2023: v. 1.2.86 (10-10-2022). The installer prompted for an install location, with a default of ~/GOG Games/Into the Breach. I chose the default location and let the intaller create a desktop file etc. On install, it was clearly quite different to the old version I had - it had a native executable, rather than an .exe launched by Wine. It also contained all the Advanced Edition content, but I couldn't find any profile_* files in the install location.
In order to find the install location, I ran the launcher from the command line, and saw it was loading the new save game file from ~/.local/share/IntoTheBreach/. I simply copied my old save games to the new location and relaunched the game and my old profiles were available in the game!
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