diff --git a/app/src/processing/app/Problem.java b/app/src/processing/app/Problem.java
index 6a0faf380..54a5f5391 100644
--- a/app/src/processing/app/Problem.java
+++ b/app/src/processing/app/Problem.java
@@ -78,7 +78,7 @@ public interface Problem {
    * Get the exact character on which this problem ends in code line relative.
    * 
    * @return Number of characters past the start of the line if known where the
-   *    code associated with the Problem ends.
+   *    code associated with the Problem ends. If -1, should use the whole line.
    */
   public int getStopOffset();
 
diff --git a/app/src/processing/app/syntax/PdeTextAreaPainter.java b/app/src/processing/app/syntax/PdeTextAreaPainter.java
index 2c83a518b..a19fcba58 100644
--- a/app/src/processing/app/syntax/PdeTextAreaPainter.java
+++ b/app/src/processing/app/syntax/PdeTextAreaPainter.java
@@ -151,7 +151,8 @@ protected void paintErrorLine(Graphics gfx, int line, int x) {
       int lineOffsetStop = textArea.getLineStopOffset(line);
 
       int wiggleStart = lineOffsetStart + problem.getStartOffset();
-      int wiggleStop = lineOffsetStart + problem.getStopOffset();
+      int stopOffset = Editor.getProblemEditorLineStop(problem, lineOffsetStart, lineOffsetStop);
+      int wiggleStop = lineOffsetStart + stopOffset;
 
       int y = textArea.lineToY(line) + getLineDisplacement();
 
@@ -330,7 +331,8 @@ public String getToolTipText(MouseEvent event) {
         int lineEnd = textArea.getLineStopOffset(line);
 
         int errorStart = lineStart + problem.getStartOffset();
-        int errorEnd = lineStart + problem.getStopOffset();
+        int stopOffsetLine = Editor.getProblemEditorLineStop(problem, lineStart, lineEnd);
+        int errorEnd = lineStart + stopOffsetLine;
 
         int startOffset = Math.max(errorStart, lineStart) - lineStart;
         int stopOffset = Math.min(errorEnd, lineEnd) - lineStart;
diff --git a/app/src/processing/app/ui/Editor.java b/app/src/processing/app/ui/Editor.java
index 911df7a49..3babbb6df 100644
--- a/app/src/processing/app/ui/Editor.java
+++ b/app/src/processing/app/ui/Editor.java
@@ -1028,6 +1028,14 @@ static public void showChanges() {
     }
   }
 
+  static public int getProblemEditorLineStop(Problem problem, int lineStart, int lineStop) {
+    int stopOffset = problem.getStopOffset();
+    if (stopOffset == -1) {
+      stopOffset = lineStop - lineStart;
+    }
+    return stopOffset;
+  }
+
 
   // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
@@ -2563,8 +2571,11 @@ public void highlight(Problem p) {
     int tabIndex = p.getTabIndex();
     int lineNumber = p.getLineNumber();
     int lineStart = textarea.getLineStartOffset(lineNumber);
+    int lineEnd = textarea.getLineStopOffset(lineNumber);
     int tabToStartOffset = lineStart + p.getStartOffset();
-    int tabToStopOffset = lineStart + p.getStopOffset();
+
+    int lineStopOffset = getProblemEditorLineStop(p, lineStart, lineEnd);
+    int tabToStopOffset = lineStart + lineStopOffset;
     highlight(tabIndex, tabToStartOffset, tabToStopOffset);
   }
 
@@ -2631,7 +2642,8 @@ public List<Problem> findProblems(int line) {
         .filter(p -> {
           int pStartLine = p.getLineNumber();
           int lineOffset = textarea.getLineStartOffset(pStartLine);
-          int pEndOffset = lineOffset + p.getStopOffset();
+          int stopOffset = p.getStopOffset();
+          int pEndOffset = lineOffset + (stopOffset == -1 ? 0 : stopOffset);
           int pEndLine = textarea.getLineOfOffset(pEndOffset);
           
           return line >= pStartLine && line <= pEndLine;
diff --git a/java/src/processing/mode/java/ErrorChecker.java b/java/src/processing/mode/java/ErrorChecker.java
index e631fbd4f..512d71d57 100644
--- a/java/src/processing/mode/java/ErrorChecker.java
+++ b/java/src/processing/mode/java/ErrorChecker.java
@@ -199,7 +199,7 @@ static private JavaProblem convertIProblem(IProblem iproblem, PreprocSketch ps)
       String badCode = ps.getPdeCode(in);
       int line = ps.tabOffsetToTabLine(in.tabIndex, in.startTabOffset);
       JavaProblem p = JavaProblem.fromIProblem(iproblem, in.tabIndex, line, badCode);
-      p.setPDEOffsets(0, iproblem.getSourceEnd() - iproblem.getSourceStart());
+      p.setPDEOffsets(0, -1);
       return p;
     }
     return null;
diff --git a/java/src/processing/mode/java/lsp/PdeAdapter.java b/java/src/processing/mode/java/lsp/PdeAdapter.java
index 1a58f3c8e..f4f1f450d 100644
--- a/java/src/processing/mode/java/lsp/PdeAdapter.java
+++ b/java/src/processing/mode/java/lsp/PdeAdapter.java
@@ -110,6 +110,11 @@ static Offset toLineCol(String s, int offset) {
     return new Offset(line, col);
   }
 
+  static Offset toLineEndCol(String s, int offset) {
+    Offset before = toLineCol(s, offset);
+    return new Offset(before.line, Integer.MAX_VALUE);
+  }
+
   
   /**
    * Converts a tabOffset to a position within a tab
@@ -232,21 +237,32 @@ void updateProblems(List<Problem> problems) {
         int startOffset = prob.getStartOffset();
         int endOffset = prob.getStopOffset();
 
+        Position startPosition = new Position(
+          prob.getLineNumber(),
+          PdeAdapter
+            .toLineCol(code.getProgram(), startOffset)
+            .col - 1
+        );
+
+        Position stopPosition;
+        if (endOffset == -1) {
+          stopPosition = new Position(
+            prob.getLineNumber(),
+            PdeAdapter
+              .toLineEndCol(code.getProgram(), startOffset)
+              .col - 1
+          );
+        } else {
+          stopPosition = new Position(
+            prob.getLineNumber(),
+            PdeAdapter
+              .toLineCol(code.getProgram(), endOffset)
+              .col - 1
+          );
+        }
+
         Diagnostic dia = new Diagnostic(
-          new Range(
-            new Position(
-              prob.getLineNumber(),
-              PdeAdapter
-                .toLineCol(code.getProgram(), startOffset)
-                .col - 1
-            ),
-            new Position(
-              prob.getLineNumber(),
-              PdeAdapter
-                .toLineCol(code.getProgram(), endOffset)
-                .col - 1
-            )
-          ),
+          new Range(startPosition, stopPosition),
           prob.getMessage()
         );
         dia.setSeverity(