diff --git a/xP/public/xP.js b/xP/public/xP.js
index 795641d..8a117f0 100644
--- a/xP/public/xP.js
+++ b/xP/public/xP.js
@@ -1058,6 +1058,13 @@ let lastWasEscape = false
 document.addEventListener('keydown', event => {
 	event.escapePrefix = lastWasEscape
 	if (lastWasEscape) {
+		// https://www.w3.org/TR/uievents-key/#keys-modifier
+		// https://bugzilla.mozilla.org/show_bug.cgi?id=1232918
+		if (["Alt", "AltGraph", "CapsLock", "Control", "Fn", "FnLock",
+			"Meta", "NumLock", "ScrollLock", "Shift", "Symbol", "SymbolLock",
+			"Hyper", "Super", "OS"].indexOf(event.key) != -1)
+			return
+
 		lastWasEscape = false
 	} else if (event.code == 'Escape' &&
 			navigator.userAgentData?.platform === 'macOS') {