diff --git a/devtools/client/webconsole/test/browser/_webconsole.ini b/devtools/client/webconsole/test/browser/_webconsole.ini
index 3423a8efed2c..324aa2b8bae2 100644
--- a/devtools/client/webconsole/test/browser/_webconsole.ini
+++ b/devtools/client/webconsole/test/browser/_webconsole.ini
@@ -296,6 +296,7 @@ https_first_disabled = true
[browser_webconsole_insecure_passwords_web_console_warning.js]
[browser_webconsole_inspect_cross_domain_object.js]
[browser_webconsole_keyboard_accessibility.js]
+[browser_webconsole_lenient_this_warning.js]
[browser_webconsole_limit_multiline.js]
[browser_webconsole_location_debugger_link.js]
fail-if = a11y_checks # bug 1687728 frame-link-filename is not accessible
diff --git a/devtools/client/webconsole/test/browser/browser_webconsole_lenient_this_warning.js b/devtools/client/webconsole/test/browser/browser_webconsole_lenient_this_warning.js
new file mode 100644
index 000000000000..5da077ab40d6
--- /dev/null
+++ b/devtools/client/webconsole/test/browser/browser_webconsole_lenient_this_warning.js
@@ -0,0 +1,68 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Check that calling the LenientThis warning is only called when expected.
+const TEST_URI = `data:text/html;charset=utf8,${encodeURI(`
+ LenientThis warning
+ `)}`;
+
+add_task(async function() {
+ const hud = await openNewTabAndConsole(TEST_URI);
+
+ const expectedWarningMessageText =
+ "Ignoring get or set of property that has [LenientThis] ";
+
+ await SpecialPowers.spawn(gBrowser.selectedBrowser, [], function() {
+ const global = content.wrappedJSObject;
+ global.console.log(global.htmlDivElementProto);
+ });
+
+ info("Wait for a bit so any warning message could be displayed");
+ await wait(1000);
+ await waitFor(() => findConsoleAPIMessage(hud, "HTMLDivElementPrototype"));
+
+ ok(
+ !findWarningMessage(hud, expectedWarningMessageText, ".warn"),
+ "Displaying the HTMLDivElementPrototype does not trigger the LenientThis warning"
+ );
+
+ info(
+ "Call a LenientThis getter with the wrong `this` to trigger a warning message"
+ );
+ await SpecialPowers.spawn(gBrowser.selectedBrowser, [], function() {
+ content.wrappedJSObject.triggerLenientThisWarning();
+ });
+
+ await waitFor(() =>
+ findWarningMessage(hud, expectedWarningMessageText, ".warn")
+ );
+ ok(
+ true,
+ "Calling the LenientThis getter with an unexpected `this` did triggered the warning"
+ );
+
+ info(
+ "Clear the console and call the LenientThis getter with an unexpected `this` again"
+ );
+ await clearOutput(hud);
+ await SpecialPowers.spawn(gBrowser.selectedBrowser, [], function() {
+ content.wrappedJSObject.triggerLenientThisWarning();
+ });
+ info("Wait for a bit so any warning message could be displayed");
+ await wait(1000);
+ ok(
+ !findWarningMessage(hud, expectedWarningMessageText, ".warn"),
+ "Calling the LenientThis getter a second time did not trigger the warning again"
+ );
+});
diff --git a/devtools/server/actors/webconsole/webidl-unsafe-getters-names.js b/devtools/server/actors/webconsole/webidl-unsafe-getters-names.js
index 1174282b2bd0..265fd70d99d6 100644
--- a/devtools/server/actors/webconsole/webidl-unsafe-getters-names.js
+++ b/devtools/server/actors/webconsole/webidl-unsafe-getters-names.js
@@ -13,6 +13,9 @@ module.exports = [
"mozPreservesPitch",
"mozPressure",
"nearestViewportElement",
+ "onmouseenter",
+ "onmouseleave",
"onmozfullscreenchange",
"onmozfullscreenerror",
+ "onreadystatechange",
];
diff --git a/devtools/shared/webconsole/GenerateDataFromWebIdls.py b/devtools/shared/webconsole/GenerateDataFromWebIdls.py
index 689393699276..dfb64c15164a 100644
--- a/devtools/shared/webconsole/GenerateDataFromWebIdls.py
+++ b/devtools/shared/webconsole/GenerateDataFromWebIdls.py
@@ -178,7 +178,10 @@ for result in results:
not iface in DEPRECATED_INTERFACE__EXCLUDE_LIST
and not name in unsafe_getters_names
and member.isAttr()
- and member.getExtendedAttribute("Deprecated")
+ and (
+ member.getExtendedAttribute("Deprecated")
+ or member.getExtendedAttribute("LegacyLenientThis")
+ )
):
unsafe_getters_names.append(name)