Cleanup entries - Can't get it to work

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6

Just tried it on a test version and it threw an error =D It says
“Cannot invoke “java.lang.CharSequence.length()” because “this.text” is null”
Here’s the full error:

java.lang.NullPointerException: Cannot invoke "java.lang.CharSequence.length()" because "this.text" is null
	at java.base/java.util.regex.Matcher.getTextLength(Unknown Source)
	at java.base/java.util.regex.Matcher.reset(Unknown Source)
	at java.base/java.util.regex.Matcher.<init>(Unknown Source)
	at java.base/java.util.regex.Pattern.matcher(Unknown Source)
	at org.jabref@5.11.210/org.jabref.logic.cleanup.URLCleanup.cleanup(Unknown Source)
	at org.jabref@5.11.210/org.jabref.logic.cleanup.CleanupWorker.cleanup(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.cleanup.CleanupAction.doCleanup(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.cleanup.CleanupAction.cleanup(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.cleanup.CleanupAction.lambda$execute$1(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.util.BackgroundTask$2.call(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.util.BackgroundTask$2.call(Unknown Source)
	at org.jabref@5.11.210/org.jabref.gui.util.DefaultTaskExecutor$1.call(Unknown Source)
	at org.jabref.merged.module@5.11.210/javafx.concurrent.Task$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)

I tried it on the following bibtex entry:

@Misc{Martino2001,
  author   = {Martino, Ivan},
  title    = {EFFICIENCY AXIOMS FOR SIMPLICIAL COMPLEXES},
  year     = {2001},
  abstract = {We study the notion of efficiency for cooperative games on simplicial complexes. In such games, the grand coalition [n] may be forbidden, and, thus, it is a non-trivial problem to study the total number of payoff v ∆ of a cooperative game (∆, v). We address this question in the more general setting, by characterizing the individual values that satisfy the general efficient requirement, that is v gen ∆ = T ∈∆ a T v(T) for a generic assignment of real coefficients a T. The traditional and the probabilistic efficiency are treated as a special case of this general efficiency. Finally, we introduce a new notion of efficiency arising from the combinatorial and topological property of the simplicial complex ∆. The efficiency in this scenario is called simplicial and we characterize the individual values fulfilling this constraint.},
  file     = {:C\:/TestJabref/Journals/arXiv/Efficiency axioms for simplicial complexes - Ivan Martino.pdf:PDF},
  groups   = {arXiv},
  priority = {prio1},
}

Note: I tried it with and without the abstract and got the error both times.