1 files changed, 4 insertions, 1 deletions

diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
index ad19e77d..3e1d811b 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
@@ -115,7 +115,10 @@ public class ServerLauncher {
                         // If the app is packaged in the jar, serve it.
                         URI webRootUri;
                         try {
-                                webRootUri = URI.create(indexUrlInJar.toURI().toASCIIString().replaceFirst("/index.html$", "/"));
+                                webRootUri = URI.create(indexUrlInJar.toURI().toASCIIString()
+                                                .replaceFirst("/index.html$", "/")
+                                                // Enable running without warnings from a jar.
+                                                .replaceFirst("^jar:file:", "jar:file://"));
                         } catch (URISyntaxException e) {
                                 throw new IllegalStateException("Jar has invalid base resource URI", e);
                         }