This has to be an array...

composer.json

@@ -2,7 +2,7 @@
     "name": "privatebin/privatebin",
     "description": "PrivateBin is a minimalist, open source online pastebin where the server has zero knowledge of pasted data. Data is encrypted/decrypted in the browser using 256 bit AES in Galois Counter mode (GCM).",
     "type": "project",
-    "keywords": "private, secure, end-to-end-encrypted, e2e, paste, pastebin, zero, zero-knowledge, encryption, encrypted, AES",
+    "keywords": ["private", "secure", "end-to-end-encrypted", "e2e", "paste", "pastebin", "zero", "zero-knowledge", "encryption", "encrypted", "AES"]
     "homepage": "https://github.com/PrivateBin",
     "license":"zlib-acknowledgement",
     "support": {