I noticed this when using lsp-mode for C++.To reproduce the issue without lsp-mode, execute this elisp command with M-:, this will add a face to operators:
(font-lock-add-keywords 'c++-mode '(("[][~!^&\|<>:=,.\\+*/%-]" 0 'error)))
Also, bind scroll-down-line to a key, like shift-up:
(global-set-key (kbd "<S-up>") 'scroll-down-line)
Then, put the attached example.cpp into a c++ buffer, move the point to
the bottom, then press and hold shift-up. Emacs will update the window
for several scroll events, but after that it won't update the screen for
a while. Even after shift-up is released, Emacs needs several seconds to
be interactive again.
In GNU Emacs 29.0.60 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.36, cairo version 1.16.0) of 2023-03-21 built on okoska Repository revision: 7a1272168af1a5b82979efa29451147c5d867981 Repository branch: emacs-29 Windowing system distributor 'The X.Org Foundation', version 11.0.12101006 System Description: Debian GNU/Linux bookworm/sid Configured using: 'configure --with-native-compilation=aot --without-compress-install --with-json --with-xinput2 --with-xwidgets --with-tree-sitter --with-cairo' Configured features: ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG SECCOMP SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER WEBP X11 XDBE XIM XINPUT2 XPM XWIDGETS GTK3 ZLIB Important settings: value of $LC_ALL: C.UTF-8 value of $LANG: en_US.UTF-8 value of $XMODIFIERS: @im=none locale-coding-system: utf-8-unix Major mode: C++//l Minor modes in effect: tooltip-mode: t global-eldoc-mode: t show-paren-mode: t electric-indent-mode: t mouse-wheel-mode: t tool-bar-mode: t menu-bar-mode: t file-name-shadow-mode: t global-font-lock-mode: t font-lock-mode: t blink-cursor-mode: t line-number-mode: t indent-tabs-mode: t transient-mark-mode: t auto-composition-mode: t auto-encryption-mode: t auto-compression-mode: t abbrev-mode: t Load-path shadows:/home/geza/.emacs.d/elpa/transient-20230304.1149/transient hides /usr/local/share/emacs/29.0.60/lisp/transient
Features: (shadow sort mail-extr emacsbug message mailcap yank-media puny dired dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068 epg-config gnus-util text-property-search time-date mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils comp comp-cstr warnings icons subr-x rx cl-seq cl-macs gv cl-extra help-mode bytecomp byte-compile cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs cl-loaddefs cl-lib info evil-surround-autoloads scad-mode-autoloads qml-mode-autoloads evil-exchange-autoloads evil-args-autoloads cmake-font-lock-autoloads visual-fill-column-autoloads evil-textobj-anyblock-autoloads evil-visualstar-autoloads impatient-mode-autoloads volatile-highlights-autoloads maxima-autoloads evil-cleverparens-autoloads consult-dir-autoloads gnuplot-autoloads helpful-autoloads git-modes-autoloads font-lock-profiler-autoloads paredit-autoloads math-preview-autoloads modern-cpp-font-lock-autoloads column-enforce-mode-autoloads plantuml-mode-autoloads yaml-mode-autoloads magit-todos-autoloads hl-todo-autoloads treemacs-evil-autoloads define-word-autoloads paradox-autoloads highlight-quoted-autoloads rg-autoloads lsp-pyright-autoloads peep-dired-autoloads highlight-numbers-autoloads dired-filter-autoloads fold-this-autoloads eterm-256color-autoloads xterm-color-autoloads rainbow-mode-autoloads evil-org-autoloads evil-mc-autoloads doom-modeline-autoloads hungry-delete-autoloads vterm-autoloads magit-tbdiff-autoloads embark-consult-autoloads literate-calc-mode-autoloads free-keys-autoloads memory-usage-autoloads ccls-autoloads svg-tag-mode-autoloads atomic-chrome-autoloads websocket-autoloads test-simple-autoloads frog-jump-buffer-autoloads frog-menu-autoloads gcmh-autoloads elisp-refs-autoloads evil-textobj-line-autoloads yasnippet-autoloads highlight-doxygen-autoloads vertico-autoloads elfeed-autoloads consult-lsp-autoloads dired-narrow-autoloads highlight-autoloads smeargle-autoloads clean-aindent-mode-autoloads cmake-mode-autoloads string-inflection-autoloads ws-butler-autoloads ov-autoloads gif-screencast-autoloads diredfl-autoloads go-mode-autoloads centered-cursor-mode-autoloads lsp-ui-autoloads camcorder-autoloads easy-mmode org-jira-autoloads ag-autoloads queue-autoloads orderless-autoloads hide-lines-autoloads git-timemachine-autoloads csv-mode-autoloads broadcast-autoloads evil-leader-autoloads hide-mode-line-autoloads company-box-autoloads transpose-frame-autoloads lsp-treemacs-autoloads evil-textobj-entire-autoloads htmlize-autoloads dired-subtree-autoloads dired-hacks-utils-autoloads evil-multiedit-autoloads iedit-autoloads orgit-autoloads evil-textobj-column-autoloads names-autoloads advice wgrep-autoloads ninja-mode-autoloads smartparens-autoloads powerthesaurus-autoloads request-autoloads git-gutter-fringe-autoloads git-gutter-autoloads highlight-indent-guides-autoloads parent-mode-autoloads pcre2el-autoloads rust-mode-autoloads evil-snipe-autoloads fringe-helper-autoloads glsl-mode-autoloads disk-usage-autoloads highlight-symbol-autoloads git-identity-autoloads consult-flycheck-autoloads consult-autoloads shrink-path-autoloads treemacs-projectile-autoloads winum-autoloads svg-lib-autoloads org-superstar-autoloads rmsbolt-autoloads dired-git-info-autoloads all-the-icons-autoloads ob-ipython-autoloads dash-functional-autoloads evil-collection-autoloads annalist-autoloads treemacs-magit-autoloads treemacs-autoloads cfrs-autoloads pfuture-autoloads ace-window-autoloads avy-autoloads demangle-mode-autoloads frame-local-autoloads evil-anzu-autoloads anzu-autoloads evil-indent-plus-autoloads better-jumper-autoloads delight-autoloads company-autoloads projectile-autoloads marginalia-autoloads dumb-jump-autoloads popup-autoloads bm-autoloads vdiff-magit-autoloads vdiff-autoloads hydra-autoloads evil-lion-autoloads evil-autoloads goto-chg-autoloads evil-matchit-autoloads async-autoloads simple-httpd-autoloads lorem-ipsum-autoloads expand-region-autoloads shut-up-autoloads flycheck-autoloads pkg-info-autoloads epl-autoloads page-break-lines-autoloads embark-autoloads which-key-autoloads blamer-autoloads posframe-autoloads git-link-autoloads drag-stuff-autoloads code-review-autoloads emojify-autoloads forge-autoloads yaml-autoloads deferred-autoloads uuidgen-autoloads ghub-autoloads treepy-autoloads a-autoloads magit-autoloads magit-section-autoloads git-commit-autoloads with-editor-autoloads transient-autoloads closql-autoloads emacsql-autoloads compat-autoloads lsp-mode-autoloads lv-autoloads markdown-mode-autoloads spinner-autoloads ht-autoloads f-autoloads s-autoloads dash-autoloads rmc iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors frame minibuffer nadvice seq simple cl-generic indonesian philippine cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech european ethiopic indian cyrillic chinese composite emoji-zwj charscript charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp files window text-properties overlay sha1 md5 base64 format env code-pages mule custom widget keymap hashtable-print-readable backquote threads xwidget-internal dbusbind inotify lcms2 dynamic-setting system-font-setting font-render-setting cairo move-toolbar gtk x-toolkit xinput2 x multi-tty make-network-process native-compile emacs) Memory information: ((conses 16 150387 10063) (symbols 48 11460 0) (strings 32 32439 3583) (string-bytes 1 1406757) (vectors 16 19041) (vector-slots 8 386441 14177) (floats 8 38 102) (intervals 56 7894 0) (buffers 984 13))
example.cpp
Description: Text Data
--- End Message ---