bump minimum required version to 57

this is the least that supports all used features

diff --git a/manifest.json b/manifest.json
index 33b73d9337e7826829b59eacc2264d3839933b64..8f233a4a0ef24bd4ca3bf8018ddac85a1b78adb6 100644 (file)
--- a/manifest.json
+++ b/manifest.json
@@ -2,7 +2,7 @@
   "applications": {
     "gecko": {
       "id": "{8fb11c5b-84eb-4da0-9128-292eacce2dcb}",
-      "strict_min_version": "42.0"
+      "strict_min_version": "57.0"
     }
   },
   "author": "Damyan Ivanov",