JabRef 5.0--2020-03-06--2e6f433
Mac OS X 10.15.4 x86_64
Java 13.0.2

Steps to reproduce:

1. Web search IEEEXplore for anything ...
2. Exception
   org.jabref.logic.importer.FetcherException: A network error occurred
   at org.jabref/org.jabref.logic.importer.SearchBasedParserFetcher.performSearch(Unknown Source)
   at org.jabref/org.jabref.gui.importer.fetcher.WebSearchPaneViewModel.lambda$search$1(Unknown Source)
   at org.jabref/org.jabref.gui.util.BackgroundTask$1.call(Unknown Source)
   at org.jabref/org.jabref.gui.util.DefaultTaskExecutor$1.call(Unknown Source)
   at org.jabref.merged.module/javafx.concurrent.Task$TaskCallable.call(Unknown Source)
   at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
   at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
   at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
   at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
   at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
   at java.base/java.lang.Thread.run(Unknown Source)
   Caused by: java.io.IOException: Server returned HTTP response code: 403 for URL: https://ieeexploreapi.ieee.org/api/v1/search/articles?apikey=86wnawtvtc986d3wtnqynm8c&querytext=loeloe
   at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
   at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
   at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
   at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Unknown Source)
   at java.base/java.lang.reflect.Constructor.newInstance(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
   at java.base/java.security.AccessController.doPrivileged(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
   at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
   at org.jabref/org.jabref.logic.net.URLDownload.asInputStream(Unknown Source)
   ... 11 more
   Caused by: java.io.IOException: Server returned HTTP response code: 403 for URL: https://ieeexploreapi.ieee.org/api/v1/search/articles?apikey=86wnawtvtc986d3wtnqynm8c&querytext=loeloe
   at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
   at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
   at java.base/java.net.HttpURLConnection.getResponseCode(Unknown Source)
   at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
   at org.jabref/org.jabref.logic.net.URLDownload.openConnection(Unknown Source)
   ... 12 more

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