Currently if you start two hledger-web instances without specifying a different port, the second will appear to start successfully but you will be looking at data served by the first.
web: exit if an instance is already running (#226)
- pause for 0.1s before opening the browser, to ensure the app is ready
- don't open a browser if the app fails to start
- terminate the server thread more carefully on exit, may resolve some
lingering background thread issues eg on windows
Resolved in my wai-handler-launch fork on github, but not yet accepted upstream. See yesodweb/wai#541
web: update wai-handler-launch for better startup (fixes #226)