--- whitespace-tests-a.el	2017-05-12 23:11:38.000000000 +1200
+++ whitespace-tests-b.el	2017-05-15 01:55:43.000000000 +1200
@@ -47,6 +47,31 @@
     (should (equal (whitespace-tests--cleanup-string "a  \n\t \n\n")
                    "a  \n"))))
 
+(ert-deftest whitespace-tests-display-tables ()
+  "Test whitespace stores and restores the buffer display table - bug26892."
+  (with-temp-buffer
+    (whitespace-mode -1) ; turn off in case global ws mode is active
+    (let ((whitespace-style '(space-mark tab-mark newline-mark))
+          (whitespace-display-mappings '((space-mark   32 [183] [46])
+                                         (space-mark  160 [164] [95])
+                                         (newline-mark 10 [36 10])
+                                         (tab-mark      9 [187 9] [92 9])))
+          (buffer-display-table nil))
+      ;test the display table actually changes 
+      (should-not (equal nil
+                         (progn (whitespace-mode 1)
+                                buffer-display-table)))
+      ;test the display table restores correctly
+      (should (equal nil
+                     (progn (whitespace-mode -1)
+                            buffer-display-table)))
+      ;test the stored display table is preserved
+      (should (equal nil
+                     (progn (whitespace-mode 1)
+                            (whitespace-mode 1)
+                            (whitespace-mode -1)
+                            buffer-display-table))))))
+
 (provide 'whitespace-tests)
 
 ;;; whitespace-tests.el ends here