Downstream bug: https://bugzilla.redhat.com/show_bug.cgi?id=870621 "Description of problem: Specifiing command (in terminal launcher): "exo-open --launch TerminalEmulator --tab --tab --tab" result in error: exo-helper: Unknown option --tab --tab --tab. Type 'exo-helper --help' for usage. although right action should be start preferred terminal app with "--tab --tab --tab" as its parameters."
*** Bug 9315 has been marked as a duplicate of this bug. ***
*** Bug 13453 has been marked as a duplicate of this bug. ***
Sean Davis referenced this bugreport in commit 21be6acf87c8575fdbe44dd0399583c115368c5c exo-launch: pass flags to preferred application (Bug 9427), Add exo_str_is_flag to public API https://git.xfce.org/xfce/exo/commit?id=21be6acf87c8575fdbe44dd0399583c115368c5c
This should now be resolved in the above commit.