diff --git a/debug/org.eclipse.debug.tests/META-INF/MANIFEST.MF b/debug/org.eclipse.debug.tests/META-INF/MANIFEST.MF
index 9423ff5b0a1..aa3897ece18 100644
--- a/debug/org.eclipse.debug.tests/META-INF/MANIFEST.MF
+++ b/debug/org.eclipse.debug.tests/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.debug.tests;singleton:=true
-Bundle-Version: 3.15.300.qualifier
+Bundle-Version: 3.15.400.qualifier
 Bundle-Localization: plugin
 Require-Bundle: org.eclipse.ui;bundle-version="[3.6.0,4.0.0)",
  org.eclipse.core.runtime;bundle-version="[3.29.0,4.0.0)",
diff --git a/debug/org.eclipse.debug.tests/src/org/eclipse/debug/tests/console/IOConsoleTests.java b/debug/org.eclipse.debug.tests/src/org/eclipse/debug/tests/console/IOConsoleTests.java
index a255c874b31..e79a7f3e141 100644
--- a/debug/org.eclipse.debug.tests/src/org/eclipse/debug/tests/console/IOConsoleTests.java
+++ b/debug/org.eclipse.debug.tests/src/org/eclipse/debug/tests/console/IOConsoleTests.java
@@ -715,7 +715,7 @@ public void testTrim() throws Exception {
 
 				c.getConsole().setWaterMarks(50, 100);
 				c.waitForScheduledJobs();
-				c.verifyContentByOffset("0123456789", 0);
+				c.verifyContentByOffset("0123456789", 1);
 				assertTrue(c.getDocument().getNumberOfLines() < 15, "Document not trimmed.");
 			}
 			closeConsole(c);
diff --git a/debug/org.eclipse.ui.console/META-INF/MANIFEST.MF b/debug/org.eclipse.ui.console/META-INF/MANIFEST.MF
index d66f083c3a4..c63a3299d4c 100644
--- a/debug/org.eclipse.ui.console/META-INF/MANIFEST.MF
+++ b/debug/org.eclipse.ui.console/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.ui.console; singleton:=true
-Bundle-Version: 3.16.0.qualifier
+Bundle-Version: 3.16.100.qualifier
 Bundle-Activator: org.eclipse.ui.console.ConsolePlugin
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
diff --git a/debug/org.eclipse.ui.console/src/org/eclipse/ui/internal/console/IOConsolePartitioner.java b/debug/org.eclipse.ui.console/src/org/eclipse/ui/internal/console/IOConsolePartitioner.java
index 716eacbe3b8..9e1f2efc985 100644
--- a/debug/org.eclipse.ui.console/src/org/eclipse/ui/internal/console/IOConsolePartitioner.java
+++ b/debug/org.eclipse.ui.console/src/org/eclipse/ui/internal/console/IOConsolePartitioner.java
@@ -1203,6 +1203,8 @@ private void trim(int truncateOffset, boolean truncateToOffsetLineStart) {
 					if (truncateToOffsetLineStart) {
 						int cutoffLine = document.getLineOfOffset(truncateOffset);
 						cutOffset = document.getLineOffset(cutoffLine);
+						// deal with case of one long line
+						cutOffset = Math.max(cutOffset, truncateOffset);
 					}
 					if (cutOffset >= length) {
 						updateType = DocUpdateType.TRIM;