Hi folks, I am seeing this issue on emacs head. The text randomly flips vertically. Very hard to reproduce. But if you open a very long C/C++ file like https://github.com/KhronosGroup/Vulkan-Headers/blob/master/include/vulkan/vulkan_core.h and keep moving around the buffer, cut 100ish lines and paste in another location and then move around again. You might hit the issue. Here is a screenshot of it. I haven’t tried with emacs -Q yet but happy to try if required. //Wasim In GNU Emacs 28.0.50 (build 1, x86_64-apple-darwin19.4.0, NS appkit-1894.40 Version 10.15.4 (Build 19E287)) of 2020-05-06 built on Wasims-iMac-Pro.local Repository revision: 86fef6ab89ee54c6f78bc2064e55c5439e929827 Repository branch: master Windowing system distributor 'Apple', version 10.3.1894 System Description: Mac OS X 10.15.4 Recent messages: Source file ‘/Users/wasimabbas/.emacs.d/init.el’ newer than byte-compiled file; using older file Turn on helm-projectile key bindings [yas] Prepared just-in-time loading of snippets successfully. [2 times] You appear to be setting environment variables ("PATH") in your .bashrc or .zshrc: those files are only read by interactive shells, so you should instead set environment variables in startup files like .profile, .bash_profile or .zshenv. Refer to your shell’s man page for more info. Customize ‘exec-path-from-shell-arguments’ to remove "-i" when done, or disable ‘exec-path-from-shell-check-startup-files’ to disable this message. Warning: /Users/wasimabbas/.emacs.d/init.el is newer than /Users/wasimabbas/.emacs.d/init.elc For information about GNU Emacs and the GNU system, type C-h C-a. 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