Merge tools in "Resolve conflicts" not shown
Disabling the "Optimize rendering for screens with different pixel densities" ( "Options -> Environment -> General -> Optimize rendering for screens with different pixel densities (requires restart)") and restart visual studio Or Inside the "Developer Command Prompt for VS2019", type the command tf resolve This will open (from what it looks like) the same window as the one within VS2019, without styling, but the Merge buttons will are present and usable.