fix(linux): tighten portal source fallback routing

electron/ipc/register/sourceMapping.test.ts

@@ -17,16 +17,28 @@ describe("getScreenSourceIdForDisplay", () => {
 		).toBe("screen:42:0");
 	});
 
-	it("routes unmatched Linux screens through the portal sentinel", () => {
+	it("routes unmatched Linux Wayland screens through the portal sentinel", () => {
 		expect(
 			getScreenSourceIdForDisplay({
 				displayId: "42",
+				env: { XDG_SESSION_TYPE: "wayland", WAYLAND_DISPLAY: "wayland-0" },
 				matchedSourceId: null,
 				platform: "linux",
 			}),
 		).toBe(LINUX_PORTAL_SCREEN_SOURCE_ID);
 	});
 
+	it("keeps unmatched Linux X11 screens on the explicit fallback id", () => {
+		expect(
+			getScreenSourceIdForDisplay({
+				displayId: "42",
+				env: { XDG_SESSION_TYPE: "x11", DISPLAY: ":0" },
+				matchedSourceId: null,
+				platform: "linux",
+			}),
+		).toBe("screen:fallback:42");
+	});
+
 	it("keeps non-Linux unmatched screens on the explicit fallback id", () => {
 		expect(
 			getScreenSourceIdForDisplay({
@@ -59,6 +71,16 @@ describe("shouldUseSyntheticLinuxPortalSource", () => {
 		).toBe(false);
 	});
 
+	it("recovers stale fallback ids through the synthetic path on Wayland", () => {
+		expect(
+			shouldUseSyntheticLinuxPortalSource({
+				env: { WAYLAND_DISPLAY: "wayland-0" },
+				platform: "linux",
+				sourceId: "screen:fallback:0",
+			}),
+		).toBe(true);
+	});
+
 	it("defaults unknown Linux sessions with WAYLAND_DISPLAY to the synthetic path", () => {
 		expect(
 			shouldUseSyntheticLinuxPortalSource({

electron/ipc/register/sourceMapping.ts

@@ -14,10 +14,12 @@ export function isLikelyLinuxWaylandSession(env: NodeJS.ProcessEnv) {
 
 export function getScreenSourceIdForDisplay({
 	displayId,
+	env = process.env,
 	matchedSourceId,
 	platform,
 }: {
 	displayId: string;
+	env?: NodeJS.ProcessEnv;
 	matchedSourceId?: string | null;
 	platform: NodeJS.Platform | string;
 }) {
@@ -25,7 +27,7 @@ export function getScreenSourceIdForDisplay({
 		return matchedSourceId;
 	}
 
-	if (platform === "linux") {
+	if (platform === "linux" && isLikelyLinuxWaylandSession(env)) {
 		return LINUX_PORTAL_SCREEN_SOURCE_ID;
 	}
 
@@ -45,7 +47,11 @@ export function shouldUseSyntheticLinuxPortalSource({
 		return false;
 	}
 
-	if (sourceId && sourceId !== LINUX_PORTAL_SCREEN_SOURCE_ID) {
+	if (
+		sourceId &&
+		sourceId !== LINUX_PORTAL_SCREEN_SOURCE_ID &&
+		!sourceId.startsWith("screen:fallback:")
+	) {
 		return false;
 	}
 

electron/ipc/register/sources.ts

@@ -128,6 +128,7 @@ export function registerSourceHandlers({
 			return {
 				id: getScreenSourceIdForDisplay({
 					displayId,
+					env: process.env,
 					matchedSourceId: matchedSource?.id,
 					platform: process.platform,
 				}),

src/hooks/useScreenRecorder.test.ts

@@ -212,7 +212,7 @@ describe("shouldUseLinuxPortalCapture", () => {
 	it("uses the portal when the selected source is the Linux sentinel", () => {
 		expect(
 			shouldUseLinuxPortalCapture({
-				browserCaptureSourceId: "screen:0:0",
+				browserCaptureSourceId: "screen:linux-portal",
 				selectedSourceId: "screen:linux-portal",
 			}),
 		).toBe(true);
@@ -235,6 +235,15 @@ describe("shouldUseLinuxPortalCapture", () => {
 			}),
 		).toBe(false);
 	});
+
+	it("prefers a live Electron source over stale portal selection state", () => {
+		expect(
+			shouldUseLinuxPortalCapture({
+				browserCaptureSourceId: "screen:42:0",
+				selectedSourceId: "screen:linux-portal",
+			}),
+		).toBe(false);
+	});
 });
 
 describe("getScreenCaptureCursorSetting", () => {

src/hooks/useScreenRecorder.ts

@@ -135,6 +135,10 @@ export function shouldUseLinuxPortalCapture({
 	browserCaptureSourceId?: string;
 	selectedSourceId?: string;
 }) {
+	if (browserCaptureSourceId && browserCaptureSourceId !== LINUX_PORTAL_SOURCE.id) {
+		return false;
+	}
+
 	return (
 		selectedSourceId === LINUX_PORTAL_SOURCE.id ||
 		browserCaptureSourceId === LINUX_PORTAL_SOURCE.id