diff --git a/nushell_completions.go b/nushell_completions.go
index 8f7c856..c03ea8d 100644
--- a/nushell_completions.go
+++ b/nushell_completions.go
@@ -31,7 +31,7 @@ let cobra_apps = ["%[1]s"]
 
 # An external completer that works with any cobra based
 # command line application (e.g. kubectl, minikube)
-let-env cobra_completer = {|spans| 
+let cobra_completer = {|spans| 
   let cmd = $spans.0
 
   if not ($cobra_apps | where $cmd =~ $it | is-empty) {
@@ -132,6 +132,14 @@ let-env cobra_completer = {|spans|
       $completions
     }
 
+    # Cobra returns a list of completions that are supported with this directive
+    # There is no way to currently support this in a nushell external completer
+    let completions = if $directive == $ShellCompDirectiveFilterFileExt {
+      []
+    } else {
+      $completions
+    }
+
     let return_val = if $last_span =~ '=' {
       # if the completion is of the form -n= return flag as part of the completion so that it doesn't get replaced
       $completions | each {|it| $"($last_span | split row '=' | first)=($it.value)" }