diff --git a/action.yml b/action.yml
index a887b8c..4094a5a 100644
--- a/action.yml
+++ b/action.yml
@@ -82,7 +82,8 @@ runs:
         )"
         # We get a JSON with an signedUploadUrl similar to :
         #  https://entrepot.xlii.si/twirp/github.actions.results.api.v1.ArtifactService/UploadArtifact?sig=yWWEI8tIIECp8D7E5TVh4_6G2pZxWaVdQcSYaCsx5s0=&expires=2024-08-26+07%3A20%3A49.886890537+%2B0200+CEST&artifactName=mymodule-1.2.3.zip&taskID=63
-        SIGNED_UPLOAD_URL="$( echo "$RESPONSE" | sed -n 's/.*"signed_?[uU]pload_?[uU]rl" *: *"\([^"]\+\)".*/\1/p' )"
+        SIGNED_UPLOAD_URL="$( echo "$RESPONSE" | sed -n 's/.*"signed_\?[uU]pload_\?[uU]rl" *: *"\([^"]\+\)".*/\1/p' )"
+        printf "$SIGNED_UPLOAD_URL" | base64
 
         # Upload our file
         # (note: adding '&comp=block' at the end of the URL)