diff --git a/README.md b/README.md
index f26bb82c..f900383e 100644
--- a/README.md
+++ b/README.md
@@ -54,7 +54,7 @@ Jasmine tests itself across many browsers (Safari, Chrome, Firefox, Microsoft Ed
 | Node              | 10, 12, 14, 16     |
 | Safari            | 8-14               |
 | Chrome            | Evergreen          |
-| Firefox           | Evergreen, 68, 78  |
+| Firefox           | Evergreen, 68, 78, 91 |
 | Edge              | Evergreen          |
 | Internet Explorer | 10, 11             |
 
diff --git a/scripts/run-all-browsers b/scripts/run-all-browsers
index fed12b02..45d74aaa 100755
--- a/scripts/run-all-browsers
+++ b/scripts/run-all-browsers
@@ -27,6 +27,7 @@ run_browser "internet explorer" 11
 run_browser "internet explorer" 10
 run_browser chrome latest
 run_browser firefox latest
+run_browser firefox 91
 run_browser firefox 78
 run_browser firefox 68 
 run_browser safari 14