Ctrl-Backspace in vim broken after upgrade

Under FreeBSD’s xterm the following setting made vim delete the last word after pressing ctrl+← (“Control+Backspace”): set backspace=indent,eol,start inoremap cnoremap For whatever reason after the last system upgrade this does not work anymore. Instead it results in vim inserting ^? into the document. It works as expected if vim is used inside of screen. Note: - Pressing ctrl+v,ctrl+? in vim under xterm inserts ^[[27;6;63~. - Pressing ctrl+v,ctrl+? in vim under screen inserts ^?. vim --version gives: VIM - Vi IMproved 8.1 (2018 May 18, compiled Nov 24 2019 15:10:11) Included patches: 1-2237 Compiled by root@120amd64-default-job-19 Huge version with GTK3 GUI. Features included (+) or not (-): +acl -farsi +mouse_sysmouse -tag_any_white +arabic +file_in_path +mouse_urxvt -tcl +autocmd +find_in_path +mouse_xterm +termguicolors +autochdir +float +multi_byte +terminal -autoservername +folding +multi_lang +terminfo +balloon_eval -footer -mzscheme +termresponse +balloon_eval_term +fork() +netbeans_intg +textobjects +browse +gettext +num64 +textprop ++builtin_terms -hangul_input +packages +timers +byte_offset +iconv +path_extra +title +channel +insert_expand +perl +toolbar +cindent +job +persistent_undo +user_commands +clientserver +jumplist +postscript +vartabs +clipboard +keymap +printer +vertsplit +cmdline_compl +lambda +profile +virtualedit +cmdline_hist +langmap -python +visual +cmdline_info +libcall +python3 +visualextra +comments +linebreak +quickfix +viminfo +conceal +lispindent +reltime +vreplace +cryptv +listcmds +rightleft +wildignore +cscope +localmap +ruby +wildmenu +cursorbind -lua +scrollbind +windows +cursorshape +menu +signs +writebackup +dialog_con_gui +mksession +smartindent +X11 +diff +modify_fname -sound -xfontset +digraphs +mouse +spell +xim +dnd +mouseshape +startuptime +xpm -ebcdic +mouse_dec +statusline +xsmp_interact +emacs_tags -mouse_gpm -sun_workshop +xterm_clipboard +eval -mouse_jsbterm +syntax -xterm_save +ex_extra +mouse_netterm +tag_binary +extra_search +mouse_sgr -tag_old_static Any ideas how to fix this, so that ctrl+← in vim deletes the last word?