diff --git a/src/test/rustdoc-gui/theme-change.goml b/src/test/rustdoc-gui/theme-change.goml
index b1de3c366149a..cc47f1f450c5a 100644
--- a/src/test/rustdoc-gui/theme-change.goml
+++ b/src/test/rustdoc-gui/theme-change.goml
@@ -2,31 +2,66 @@
 goto: "file://" + |DOC_PATH| + "/test_docs/index.html"
 local-storage: {"rustdoc-use-system-theme": "false", "rustdoc-theme": "dark"}
 reload:
+
+store-value: (background_light, "rgb(255, 255, 255)")
+store-value: (background_dark, "rgb(53, 53, 53)")
+store-value: (background_ayu, "rgb(15, 20, 25)")
+
 click: "#settings-menu"
 wait-for: "#theme-ayu"
 click: "#theme-ayu"
 // should be the ayu theme so let's check the color.
-wait-for-css: ("body", { "background-color": "rgb(15, 20, 25)" })
+wait-for-css: ("body", { "background-color": |background_ayu| })
 assert-local-storage: { "rustdoc-theme": "ayu" }
 click: "#theme-light"
 // should be the light theme so let's check the color.
-wait-for-css: ("body", { "background-color": "rgb(255, 255, 255)" })
+wait-for-css: ("body", { "background-color": |background_light| })
 assert-local-storage: { "rustdoc-theme": "light" }
 click: "#theme-dark"
 // Should be the dark theme so let's check the color.
-wait-for-css: ("body", { "background-color": "rgb(53, 53, 53)" })
+wait-for-css: ("body", { "background-color": |background_dark| })
 assert-local-storage: { "rustdoc-theme": "dark" }
 
+local-storage: {
+    "rustdoc-preferred-light-theme": "light",
+    "rustdoc-preferred-dark-theme": "light",
+}
 goto: "file://" + |DOC_PATH| + "/settings.html"
+
 wait-for: "#settings"
 click: "#theme-light"
-wait-for-css: ("body", { "background-color": "rgb(255, 255, 255)" })
+wait-for-css: ("body", { "background-color": |background_light| })
 assert-local-storage: { "rustdoc-theme": "light" }
 
 click: "#theme-dark"
-wait-for-css: ("body", { "background-color": "rgb(53, 53, 53)" })
+wait-for-css: ("body", { "background-color": |background_dark| })
 assert-local-storage: { "rustdoc-theme": "dark" }
 
 click: "#theme-ayu"
-wait-for-css: ("body", { "background-color": "rgb(15, 20, 25)" })
+wait-for-css: ("body", { "background-color": |background_ayu| })
 assert-local-storage: { "rustdoc-theme": "ayu" }
+
+assert-local-storage-false: { "rustdoc-use-system-theme": "true" }
+click: "#theme-system-preference"
+wait-for: ".setting-line:not(.hidden) #preferred-light-theme"
+assert-local-storage: { "rustdoc-use-system-theme": "true" }
+// We click on both preferred light and dark themes to be sure that there is a change.
+click: "#preferred-light-theme-dark"
+click: "#preferred-dark-theme-dark"
+wait-for-css: ("body", { "background-color": |background_dark| })
+
+reload:
+// Ensure that the "preferred themes" are still displayed.
+wait-for: ".setting-line:not(.hidden) #preferred-light-theme"
+click: "#theme-light"
+wait-for-css: ("body", { "background-color": |background_light| })
+assert-local-storage: { "rustdoc-theme": "light" }
+// Ensure it's now hidden again
+wait-for: ".setting-line.hidden #preferred-light-theme"
+// And ensure the theme was rightly set.
+wait-for-css: ("body", { "background-color": |background_light| })
+assert-local-storage: { "rustdoc-theme": "light" }
+
+reload:
+wait-for: "#settings"
+assert: ".setting-line.hidden #preferred-light-theme"