It is common practice to do some things before/after debugging (manipulation with resources, watching some changes, etc.).
Theia should recognize preLaunchTask and postDebugTask parameters from debugger configuration file (launch.json).
@mmorhun is this something VS Code supports? If yes, can you reference some doc?
Yes, that's comes from VSCode. Docs are here.
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Yes, that's comes from VSCode. Docs are here.