Release 176 contained a fix for misc CoreText renderer bugs and glitches (#1356), and the fix for clipping is causing some performance regressions. You can tell this is happening just by scrolling. We should fix the bug. Not getting clipped text is important but it shouldn't have caused the regression. Meanwhile, if users are encountering this, they can do `defaults write org.vim.MacVim MMRendererClipToRow 1` to temporarily work around it (this just makes it work like before, where tall texts would get clipped), but they should unset it once the fix is in.