I don't have a good recipe for this. It has been happening occasionally for quite some time (the attached screenshots are from 2021, but the same thing is still occurring). Every once in a while, a part of the Emacs frame gets into a state where glyphs from nearby lines can be painted after the tail end of other lines. This seems to be related to scrolling (that is, while scrolling, the glyphs replicate onto nearby lines, but when scrolling back they stay. I usually have to force a full repaint to get the glyphs to disappear.
CleanShot 2021-10-27 at 22.35.25@2x.png
Description: PNG image
CleanShot 2021-10-27 at 22.35.35@2x.png
Description: PNG image
In GNU Emacs 30.0.50 (build 1, aarch64-apple-darwin22.4.0, NS appkit-2299.50 Version 13.3.1 (Build 22E261)) of 2023-04-09 built on Aarons-Laptop.local Windowing system distributor 'Apple', version 10.3.2299 System Description: macOS 13.3.1 Configured using: 'configure --disable-dependency-tracking --disable-silent-rules --enable-locallisppath=/opt/homebrew/share/emacs/site-lisp --infodir=/opt/homebrew/Cellar/emacs-plus@30/30.0.50/share/info/emacs --prefix=/opt/homebrew/Cellar/emacs-plus@30/30.0.50 --with-xml2 --with-gnutls --with-native-compilation --without-compress-install --without-dbus --without-imagemagick --with-modules --with-rsvg --with-ns --disable-ns-self-contained 'CFLAGS=-Os -w -pipe -mmacosx-version-min=13 -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX13.sdk -DFD_SETSIZE=10000 -DDARWIN_UNLIMITED_SELECT' 'CPPFLAGS=-I/opt/homebrew/opt/zlib/include -I/opt/homebrew/opt/jpeg/include -I/opt/homebrew/opt/icu4c/include -I/opt/homebrew/opt/openssl@1.1/include -isystem/opt/homebrew/include -F/opt/homebrew/Frameworks -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX13.sdk' 'LDFLAGS=-L/opt/homebrew/opt/zlib/lib -L/opt/homebrew/opt/jpeg/lib -L/opt/homebrew/opt/icu4c/lib -L/opt/homebrew/opt/openssl@1.1/lib -L/opt/homebrew/lib -F/opt/homebrew/Frameworks -Wl,-headerpad_max_install_names -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX13.sdk'' Configured features: ACL GIF GLIB GMP GNUTLS JPEG JSON LCMS2 LIBXML2 MODULES NATIVE_COMP NOTIFY KQUEUE NS PDUMPER PNG RSVG SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XIM ZLIB Important settings: value of $LANG: en_US.UTF-8 locale-coding-system: utf-8-unix Major mode: ELisp/d Minor modes in effect: global-evil-mc-mode: t evil-mc-mode: t treemacs-filewatch-mode: t treemacs-follow-mode: t treemacs-git-mode: t treemacs-fringe-indicator-mode: t global-git-commit-mode: t transient-posframe-mode: t windmove-mode: t global-flycheck-mode: t flycheck-mode: t gcmh-mode: t undo-fu-session-global-mode: t undo-fu-session-mode: t ws-butler-global-mode: t ws-butler-mode: t ns-auto-titlebar-mode: t global-anzu-mode: t anzu-mode: t corfu-prescient-mode: t corfu-history-mode: t corfu-mode: t form-feed-mode: t eval-sexp-fu-flash-mode: t eros-mode: t lispyville-mode: t lispy-mode: t elisp-def-mode: t sotlisp-mode: t speed-of-thought-mode: t electric-pair-mode: t envrc-mode: t global-evil-surround-mode: t evil-surround-mode: t evil-matchit-mode: t evil-vimish-fold-mode: t vimish-fold-mode: t dtrt-indent-mode: t tabspaces-mode: t save-place-mode: t winner-mode: t savehist-mode: t delete-selection-mode: t yas-global-mode: t yas-minor-mode: t vertico-prescient-mode: t prescient-persist-mode: t vertico-mouse-mode: t vertico-mode: t mini-frame-mode: t better-jumper-mode: t better-jumper-local-mode: t xterm-mouse-mode: t pixel-scroll-precision-mode: t global-auto-revert-mode: t which-key-posframe-mode: t which-key-mode: t org-roam-db-autosync-mode: t shell-dirtrack-mode: t recentf-mode: t repeat-mode: t +popup-mode: t evil-mode: t evil-local-mode: t nano-modeline-mode: t server-mode: t leader-key-leader-override-mode: t global-leader-key-leader-override-mode: t elpaca-use-package-mode: t override-global-mode: t global-display-line-numbers-mode: t display-line-numbers-mode: t global-eldoc-mode: t eldoc-mode: t show-paren-mode: t electric-indent-mode: t mouse-wheel-mode: t tab-bar-mode: t file-name-shadow-mode: t global-font-lock-mode: t font-lock-mode: t window-divider-mode: t line-number-mode: t auto-fill-function: yas--auto-fill transient-mark-mode: t auto-composition-mode: t auto-encryption-mode: t auto-compression-mode: t abbrev-mode: t
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