diff --git a/antlr4-maven-plugin/src/main/java/org/antlr/mojo/antlr4/Antlr4Mojo.java b/antlr4-maven-plugin/src/main/java/org/antlr/mojo/antlr4/Antlr4Mojo.java
index c0926fe6c..472b0147c 100644
--- a/antlr4-maven-plugin/src/main/java/org/antlr/mojo/antlr4/Antlr4Mojo.java
+++ b/antlr4-maven-plugin/src/main/java/org/antlr/mojo/antlr4/Antlr4Mojo.java
@@ -55,7 +55,7 @@ import java.util.Set;
 	name = "antlr4",
 	defaultPhase = LifecyclePhase.GENERATE_SOURCES,
 	requiresDependencyResolution = ResolutionScope.COMPILE,
-	requiresProject = true)
+	requiresProject = true, threadSafe = true)
 public class Antlr4Mojo extends AbstractMojo {
 
     // First, let's deal with the options that the ANTLR tool itself
diff --git a/contributors.txt b/contributors.txt
index 5f6eb26bc..1ba682f00 100644
--- a/contributors.txt
+++ b/contributors.txt
@@ -287,4 +287,6 @@ YYYY/MM/DD, github id, Full name, email
 2021/01/25, l215884529, Qiheng Liu, 13607681+l215884529@users.noreply.github.com
 2021/02/02, tsotnikov, Taras Sotnikov, taras.sotnikov@gmail.com
 2021/02/21, namasikanam, Xingyu Xie, namasikanam@gmail.com
+2021/02/27, khmarbaise, Karl Heinz Marbaise, github@soebes.com
 2021/03/01, preethamrn, Preetham Narayanareddy, preetham.narayanareddy@gmail.com
+2021/03/02, hackeris
diff --git a/doc/javascript-target.md b/doc/javascript-target.md
index da01ca2a2..f5d7658fb 100644
--- a/doc/javascript-target.md
+++ b/doc/javascript-target.md
@@ -91,7 +91,7 @@ Now a fully functioning script might look like the following:
 
 ```javascript
    import antlr4 from 'antlr4';
-   import MyGrammarLexer from './MyGrammarLexer.js');
+   import MyGrammarLexer from './MyGrammarLexer.js';
    import MyGrammarParser from './MyGrammarParser.js';
    import MyGrammarListener from './MyGrammarListener.js';