Most probably the same cause as in https://github.com/geany/geany/issues/3149.
Please note that even if the backtrace puts `vte_send_cmd()` in a prominent position, the crash there is only a symptom of the underlying problem that `vc->send_cmd_prefix` is `NULL` because its fallback value is not applied when read from the config.
@overcq as a workaround, the crashes should stop if you disable the 'Follow path of current file' option in VTE preferences.