Merge pull request #627 from marp-team/stable-preview-window-detector

Make the preview option stable against occasional invalid URL errors

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Make the preview option stable against occasional invalid URL errors ([#627](https://github.com/marp-team/marp-cli/pull/627))
+
 ## v4.0.4 - 2024-12-25
 
 ### Added

src/preview.ts

@@ -165,15 +165,17 @@ export class Preview extends (EventEmitter as new () => TypedEmitter<Preview.Eve
           const idMatcher = (target: Target) => {
             debugPreview('Activated the window finder for %s.', id)
 
-            const url = new URL(target.url())
+            if (target.type() === 'page') {
+              const url = new URL(target.url())
 
-            if (url.searchParams.get('__marp_cli_id') === id) {
-              debugPreview('Found a target window with id: %s', id)
-              pptr.off('targetcreated', idMatcher)
+              if (url.searchParams.get('__marp_cli_id') === id) {
+                debugPreview('Found a target window with id: %s', id)
+                pptr.off('targetcreated', idMatcher)
 
-              void (async () => {
-                res((await target.page()) ?? (await target.asPage()))
-              })()
+                void (async () => {
+                  res((await target.page()) ?? (await target.asPage()))
+                })()
+              }
             }
           }