Unfortunatley Alacritty has the same issues: From Alacritty's FAQ: Q: "macOS + tmux + vim is slow! I thought this was supposed to be fast! This appears to be a

Unfortunatley Alacritty has the same issues: From Alacritty's FAQ: Q: "macOS + tmux + vim is slow! I thought this was supposed to be fast! This appears to be an issue outside of terminal emulators; either macOS has an IPC performance issue, or either tmux or vim (or both) have a bug. This same issue can be seen in iTerm2 and Terminal.app. I've found that if tmux is running on another machine which is connected to Alacritty via SSH, this issue disappears. Actual throughput and rendering performance are still better in Alacritty."