- Add selection_acquire, selection_release, platform_init to
W_ViewBackend struct (were used but not declared).
- Add lookup_string to W_FontBackend struct (same issue).
- Guard selection_acquire call with NULL check in selection.c.
- Remove pixman_image_unref in wl_frame_configure resize path —
wlroots manages the buffer lifecycle via scene refcounting.
LSan confirms no leak.
- Remove #include of wmspec.c/xdnd.c/xmodifier.c from x11_backend.c
— they are already compiled as standalone objects, causing
multiple-definition linker errors on clean builds.
- WINGsP.h: add selection_acquire/release slots to W_ViewBackend
- wview_x11.c: implement via XSetSelectionOwner/XGetSelectionOwner
- wview_wl.c: stub that returns True (TODO: wl_data_device)
- selection.c: use vtable instead of direct X11 calls