From b3ab47a594767ec954425d28a182e0c73262e006 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Mon, 7 Nov 2022 14:00:00 +0100
Subject: [PATCH] eframe: warn if web_sys_unstable_apis was not set

---
 crates/eframe/src/web/backend.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/crates/eframe/src/web/backend.rs b/crates/eframe/src/web/backend.rs
index b153e5c3..c4fcaf20 100644
--- a/crates/eframe/src/web/backend.rs
+++ b/crates/eframe/src/web/backend.rs
@@ -526,6 +526,11 @@ pub async fn start(
     web_options: crate::WebOptions,
     app_creator: epi::AppCreator,
 ) -> Result<AppRunnerRef, JsValue> {
+    #[cfg(not(web_sys_unstable_apis))]
+    tracing::warn!(
+        "eframe compiled without RUSTFLAGS='--cfg=web_sys_unstable_apis'. Copying text won't work."
+    );
+
     let mut runner = AppRunner::new(canvas_id, web_options, app_creator).await?;
     runner.warm_up()?;
     start_runner(runner)