From tmux-yank plugin
set -g @override_copy_command 'WAYLAND_DEBUG=1 wl-copy 2>~/$(date -u +"%H:%S")_tmux_wlcopy.log'
I copy something twice. It should replace the first wl-copy process.

First

[3671083.532]  -> wl_display@1.get_registry(new id wl_registry@2)
[3671083.624]  -> wl_display@1.sync(new id wl_callback@3)
[3671083.871] wl_display@1.delete_id(3)
[3671083.897] wl_registry@2.global(1, "wl_shm", 1)
[3671083.940]  -> wl_registry@2.bind(1, "wl_shm", 1, new id [unknown]@4)
[3671083.999] wl_registry@2.global(2, "zwp_linux_dmabuf_v1", 3)
[3671084.040] wl_registry@2.global(3, "wl_drm", 2)
[3671084.082] wl_registry@2.global(4, "wl_compositor", 4)
[3671084.123]  -> wl_registry@2.bind(4, "wl_compositor", 3, new id [unknown]@5)
[3671084.181] wl_registry@2.global(5, "wl_subcompositor", 1)
[3671084.223] wl_registry@2.global(6, "wl_data_device_manager", 3)
[3671084.265]  -> wl_registry@2.bind(6, "wl_data_device_manager", 1, new id [unknown]@6)
[3671084.323] wl_registry@2.global(7, "gamma_control_manager", 1)
[3671084.364] wl_registry@2.global(8, "zwlr_gamma_control_manager_v1", 1)
[3671084.406] wl_registry@2.global(9, "gtk_primary_selection_device_manager", 1)
[3671084.448]  -> wl_registry@2.bind(9, "gtk_primary_selection_device_manager", 1, new id [unknown]@7)
[3671084.506] wl_registry@2.global(10, "zxdg_output_manager_v1", 2)
[3671084.547] wl_registry@2.global(11, "org_kde_kwin_idle", 1)
[3671084.589] wl_registry@2.global(12, "zwp_idle_inhibit_manager_v1", 1)
[3671084.630] wl_registry@2.global(13, "zwlr_layer_shell_v1", 1)
[3671084.672] wl_registry@2.global(14, "zxdg_shell_v6", 1)
[3671084.713] wl_registry@2.global(15, "xdg_wm_base", 2)
[3671084.755]  -> wl_registry@2.bind(15, "xdg_wm_base", 1, new id [unknown]@8)
[3671084.813] wl_registry@2.global(16, "org_kde_kwin_server_decoration_manager", 1)
[3671084.855] wl_registry@2.global(17, "zxdg_decoration_manager_v1", 1)
[3671084.914] wl_registry@2.global(18, "zwp_relative_pointer_manager_v1", 1)
[3671084.955] wl_registry@2.global(19, "zwp_pointer_constraints_v1", 1)
[3671084.997] wl_registry@2.global(20, "wp_presentation", 1)
[3671085.038] wl_registry@2.global(21, "zwlr_export_dmabuf_manager_v1", 1)
[3671085.079] wl_registry@2.global(22, "zwlr_screencopy_manager_v1", 1)
[3671085.121] wl_registry@2.global(23, "zwlr_data_control_manager_v1", 2)
[3671085.162] wl_registry@2.global(24, "zwp_virtual_keyboard_manager_v1", 1)
[3671085.204] wl_registry@2.global(25, "zwlr_input_inhibit_manager_v1", 1)
[3671085.245] wl_registry@2.global(26, "wl_seat", 6)
[3671085.287]  -> wl_registry@2.bind(26, "wl_seat", 1, new id [unknown]@9)
[3671085.346] wl_registry@2.global(27, "wl_output", 3)
[3671085.387] wl_callback@3.done(10167)
[3671085.408]  -> wl_data_device_manager@6.get_data_device(new id wl_data_device@3, wl_seat@9)
[3671085.445]  -> gtk_primary_selection_device_manager@7.get_device(new id gtk_primary_selection_device@10, wl_seat@9)
[3671136.530]  -> wl_data_device_manager@6.create_data_source(new id wl_data_source@11)
[3671136.941]  -> wl_data_source@11.offer("text/plain")
[3671136.978]  -> wl_data_source@11.offer("text/plain;charset=utf-8")
[3671137.000]  -> wl_data_source@11.offer("TEXT")
[3671137.021]  -> wl_data_source@11.offer("STRING")
[3671137.041]  -> wl_data_source@11.offer("UTF8_STRING")
[3671137.066]  -> wl_display@1.sync(new id wl_callback@12)
[3671137.302] wl_display@1.delete_id(12)
[3671137.334] wl_seat@9.capabilities(3)
[3671137.356]  -> wl_seat@9.get_keyboard(new id wl_keyboard@13)
[3671137.384] wl_callback@12.done(10167)
[3671137.409]  -> wl_data_device@3.set_selection(wl_data_source@11, 10167)
[3671137.682] wl_keyboard@13.keymap(1, fd 4, 48469)


Second

[3672169.359]  -> wl_display@1.get_registry(new id wl_registry@2)
[3672169.442]  -> wl_display@1.sync(new id wl_callback@3)
[3672169.560] wl_display@1.delete_id(3)
[3672169.587] wl_registry@2.global(1, "wl_shm", 1)
[3672169.638]  -> wl_registry@2.bind(1, "wl_shm", 1, new id [unknown]@4)
[3672169.704] wl_registry@2.global(2, "zwp_linux_dmabuf_v1", 3)
[3672169.752] wl_registry@2.global(3, "wl_drm", 2)
[3672169.799] wl_registry@2.global(4, "wl_compositor", 4)
[3672169.846]  -> wl_registry@2.bind(4, "wl_compositor", 3, new id [unknown]@5)
[3672169.911] wl_registry@2.global(5, "wl_subcompositor", 1)
[3672169.958] wl_registry@2.global(6, "wl_data_device_manager", 3)
[3672170.005]  -> wl_registry@2.bind(6, "wl_data_device_manager", 1, new id [unknown]@6)
[3672170.071] wl_registry@2.global(7, "gamma_control_manager", 1)
[3672170.118] wl_registry@2.global(8, "zwlr_gamma_control_manager_v1", 1)
[3672170.165] wl_registry@2.global(9, "gtk_primary_selection_device_manager", 1)
[3672170.266]  -> wl_registry@2.bind(9, "gtk_primary_selection_device_manager", 1, new id [unknown]@7)
[3672170.332] wl_registry@2.global(10, "zxdg_output_manager_v1", 2)
[3672170.379] wl_registry@2.global(11, "org_kde_kwin_idle", 1)
[3672170.425] wl_registry@2.global(12, "zwp_idle_inhibit_manager_v1", 1)
[3672170.472] wl_registry@2.global(13, "zwlr_layer_shell_v1", 1)
[3672170.534] wl_registry@2.global(14, "zxdg_shell_v6", 1)
[3672170.581] wl_registry@2.global(15, "xdg_wm_base", 2)
[3672170.629]  -> wl_registry@2.bind(15, "xdg_wm_base", 1, new id [unknown]@8)
[3672170.695] wl_registry@2.global(16, "org_kde_kwin_server_decoration_manager", 1)
[3672170.742] wl_registry@2.global(17, "zxdg_decoration_manager_v1", 1)
[3672170.789] wl_registry@2.global(18, "zwp_relative_pointer_manager_v1", 1)
[3672170.836] wl_registry@2.global(19, "zwp_pointer_constraints_v1", 1)
[3672170.883] wl_registry@2.global(20, "wp_presentation", 1)
[3672170.930] wl_registry@2.global(21, "zwlr_export_dmabuf_manager_v1", 1)
[3672170.977] wl_registry@2.global(22, "zwlr_screencopy_manager_v1", 1)
[3672171.024] wl_registry@2.global(23, "zwlr_data_control_manager_v1", 2)
[3672171.071] wl_registry@2.global(24, "zwp_virtual_keyboard_manager_v1", 1)
[3672171.118] wl_registry@2.global(25, "zwlr_input_inhibit_manager_v1", 1)
[3672171.165] wl_registry@2.global(26, "wl_seat", 6)
[3672171.212]  -> wl_registry@2.bind(26, "wl_seat", 1, new id [unknown]@9)
[3672171.278] wl_registry@2.global(27, "wl_output", 3)
[3672171.325] wl_callback@3.done(10169)
[3672171.349]  -> wl_data_device_manager@6.get_data_device(new id wl_data_device@3, wl_seat@9)
[3672171.392]  -> gtk_primary_selection_device_manager@7.get_device(new id gtk_primary_selection_device@10, wl_seat@9)
[3672221.678]  -> wl_data_device_manager@6.create_data_source(new id wl_data_source@11)
[3672221.802]  -> wl_data_source@11.offer("text/plain")
[3672221.825]  -> wl_data_source@11.offer("text/plain;charset=utf-8")
[3672221.849]  -> wl_data_source@11.offer("TEXT")
[3672221.872]  -> wl_data_source@11.offer("STRING")
[3672221.895]  -> wl_data_source@11.offer("UTF8_STRING")
[3672221.960]  -> wl_display@1.sync(new id wl_callback@12)
[3672222.124] wl_display@1.delete_id(12)
[3672222.156] wl_seat@9.capabilities(3)
[3672222.179]  -> wl_seat@9.get_keyboard(new id wl_keyboard@13)
[3672222.212] wl_callback@12.done(10169)
[3672222.238]  -> wl_data_device@3.set_selection(wl_data_source@11, 10169)
[3672222.481] wl_keyboard@13.keymap(1, fd 4, 48469)