1 files changed, 15 insertions, 0 deletions
diff --git a/packages/frontend/src/utility/isWebpSupported.ts b/packages/frontend/src/utility/isWebpSupported.ts
new file mode 100644
index 0000000000..affd81fd57
--- /dev/null
+++ b/packages/frontend/src/utility/isWebpSupported.ts
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+let isWebpSupportedCache: boolean | undefined;
+export function isWebpSupported() {
+	if (isWebpSupportedCache === undefined) {
+		const canvas = window.document.createElement('canvas');
+		canvas.width = 1;
+		canvas.height = 1;
+		isWebpSupportedCache = canvas.toDataURL('image/webp').startsWith('data:image/webp');
+	}
+	return isWebpSupportedCache;
+}