diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index e4322948..7c9bc7a1 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -12,11 +12,11 @@ on:
 
 jobs:
   test:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
     name: OTP ${{matrix.otp}}
     strategy:
       matrix:
-        otp: [20.3.8.26, 21.3.8.17, 22.3.4.9, 23.3.1, 24.0.5]
+        otp: [22.3.4.9, 23.3.4.5, 24.3.3, 25.3]
         emacs: [27.1] # 24.5, 26.3,
 
     steps:
diff --git a/elisp/edts/edts-shell.el b/elisp/edts/edts-shell.el
index ceb6001b..4e651641 100644
--- a/elisp/edts/edts-shell.el
+++ b/elisp/edts/edts-shell.el
@@ -143,7 +143,9 @@ PWD and running COMMAND."
   (ignore-errors
     (make-local-variable 'show-paren-mode)
     (show-paren-mode 1))
-  (linum-mode -1)
+  (if (version<= "26.0.50" emacs-version)
+      (display-line-numbers-mode -1)
+    (linum-mode -1))
   (setq show-trailing-whitespace nil)
   (set-process-query-on-exit-flag (get-buffer-process (current-buffer)) nil)
   (add-hook 'kill-buffer-hook #'edts-shell--kill-buffer-hook t t)