diff --git a/chrome/content/zotero/platformKeys.js b/chrome/content/zotero/platformKeys.js
index 148615c965..38502b3760 100644
--- a/chrome/content/zotero/platformKeys.js
+++ b/chrome/content/zotero/platformKeys.js
@@ -40,6 +40,72 @@ window.addEventListener('DOMContentLoaded', () => {
 		if (fileQuitItemUnix) fileQuitItemUnix.hidden = true;
 		if (editPreferencesSeparator) editPreferencesSeparator.hidden = true;
 		if (editPreferencesItem) editPreferencesItem.hidden = true;
+
+		// macOS 15 Sequoia has a new system keyboard shortcut, Ctrl-Enter,
+		// that shows a context menu on the focused control. Firefox currently
+		// doesn't handle it very well - it shows a context menu on the element
+		// in the middle of the window, whatever element that may be.
+		// Prevent/retarget these events (but not Ctrl-clicks).
+		let lastPreventedContextMenuTime = 0;
+		document.addEventListener('contextmenu', (event) => {
+			if (!(event.button === 2 && event.buttons === 0 && !event.ctrlKey)) {
+				return;
+			}
+			
+			event.stopPropagation();
+			event.stopImmediatePropagation();
+			event.preventDefault();
+			
+			// We usually get three of these in a row - only act on the first
+			if (event.timeStamp - lastPreventedContextMenuTime < 50) {
+				return;
+			}
+			lastPreventedContextMenuTime = event.timeStamp;
+			
+			let targetElement = document.activeElement;
+			if (!targetElement) {
+				return;
+			}
+			if (targetElement.hasAttribute('aria-activedescendant')) {
+				let activeDescendant = targetElement.querySelector(
+					'#' + CSS.escape(targetElement.getAttribute('aria-activedescendant'))
+				);
+				if (activeDescendant) {
+					targetElement = activeDescendant;
+				}
+			}
+			
+			let [clientX, clientY] = Zotero.Utilities.Internal.getContextMenuPosition(targetElement);
+			let screenX = window.mozInnerScreenX + clientX;
+			let screenY = window.mozInnerScreenY + clientY;
+			
+			// Run in the next tick, because otherwise our rate-limiting above
+			// prevents this from working on form fields (somehow)
+			setTimeout(() => {
+				targetElement.dispatchEvent(new PointerEvent('contextmenu', {
+					bubbles: true,
+					cancelable: true,
+					button: 2,
+					buttons: 2,
+					clientX,
+					clientY,
+					layerX: clientX, // Wrong, but nobody should ever use these
+					layerY: clientY,
+					screenX,
+					screenY,
+				}));
+			});
+		}, { capture: true });
+		
+		// Make sure the Ctrl-Enter isn't handled by listeners further down in
+		// the tree as a regular Enter
+		document.documentElement.addEventListener('keydown', (event) => {
+			if (event.ctrlKey && event.key === 'Enter') {
+				event.stopPropagation();
+				event.stopImmediatePropagation();
+				event.preventDefault();
+			}
+		}, { capture: true });
 	}
 	else {
 		// Set behavior on all non-macOS platforms
diff --git a/chrome/content/zotero/xpcom/utilities_internal.js b/chrome/content/zotero/xpcom/utilities_internal.js
index 64c5284366..b510598ff5 100644
--- a/chrome/content/zotero/xpcom/utilities_internal.js
+++ b/chrome/content/zotero/xpcom/utilities_internal.js
@@ -2482,6 +2482,66 @@ Zotero.Utilities.Internal = {
 		}
 
 		return textContent;
+	},
+
+	/**
+	 * 
+	 * @param {Element} targetElement
+	 * @returns {[number, number]} clientX and clientY
+	 */
+	getContextMenuPosition(targetElement) {
+		let selection;
+		if (targetElement.editor?.selection) {
+			selection = targetElement.editor.selection;
+			if (!selection.rangeCount) {
+				selection = null;
+			}
+		}
+		else {
+			selection = targetElement.ownerDocument.getSelection();
+			if (!selection.rangeCount || !targetElement.contains(selection.getRangeAt(0).startContainer)) {
+				selection = null;
+			}
+		}
+
+		let rect;
+		let anchorToBottom;
+		let anchorToEnd;
+		if (selection) {
+			let range = selection.getRangeAt(0);
+			if (range.getClientRects().length) {
+				rect = range.getBoundingClientRect();
+			}
+			// If the selection is between lines in an editor, it'll be
+			// inside the editor's native anonymous text node and won't
+			// have any rects for some reason.
+			// If that's the case, use the text node's bounds.
+			else if (range.startContainer === range.endContainer && range.startContainer.isNativeAnonymous
+					&& range.startContainer.firstChild?.nodeType === Node.TEXT_NODE) {
+				let quads = range.startContainer.firstChild.getBoxQuads();
+				rect = quads[quads.length - 1].getBounds();
+			}
+			else {
+				rect = range.commonAncestorContainer.getBoundingClientRect();
+			}
+			anchorToBottom = !range.collapsed;
+			anchorToEnd = range.collapsed;
+		}
+		else {
+			rect = targetElement.getBoundingClientRect();
+			anchorToBottom = true;
+			anchorToEnd = false;
+		}
+
+		let clientX;
+		if (Zotero.rtl) {
+			clientX = rect.x + (anchorToEnd ? 0 : rect.width - 3);
+		}
+		else {
+			clientX = rect.x + (anchorToEnd ? rect.width + 3 : 0);
+		}
+		let clientY = rect.y + (anchorToBottom ? rect.height + 8 : 5);
+		return [clientX, clientY];
 	}
 };