I don't know much about vim, but from the report it sounds like part of the issue was that disabling modelines would not prevent it: > tabpanel is missing P_ML

I don't know much about vim, but from the report it sounds like part of the issue was that disabling modelines would not prevent it: > tabpanel is missing P_MLE Unlike statusline and tabline, tabpanel is not marked with the P_MLE flag. This allows a modeline to inject %{...} expressions even when modelineexpr is disabled. Edit: Upon re-reading the above I guess disabling modelineexpr is not the same as disabling modelines, and disabling modelines altogether might indeed prevent the issue.