Increase or make configurable the 5s timeout in HiddenBrowser.mjs
When importing items from RSS feeds on public administration / institutional repositories (which can take 6–10s on cold loads), the 5000ms hardcoded timeout in HiddenBrowser.mjs causes Page never loaded in hidden browser errors, aborting the import. Increasing this timeout to 15s (tested editing omni.ja) or making it configurable via Zotero.Prefs would solve the issue.
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