Hi, I found that this specific line break syntax highlighting in org v9.4 : #+BEGIN_SRC nix systemd.user.sessionVariables.NIX_PATH = lib.mkForce "nixpkgs=$HOME/nixpkgs\${NIX_PATH:+:}$NIX_PATH"; #+END_SRC I suppose this is a bug localized on regex parsing, removing backslash here "\${NIX_PATH:+:}" repair the problem Best regards, -- Sébastien Rey-Coyrehourcq Research Engineer UMR IDEES 02.35.14.69.30 {Stronger security for your email, follow EFF tutorial : https://ssd.eff.org/}