Index: generic/tkTextDisp.c
==================================================================
--- generic/tkTextDisp.c
+++ generic/tkTextDisp.c
@@ -7739,15 +7739,15 @@
 
 	TkrTextIndexBackBytes(textPtr, indexPtr, info.byteOffset, indexPtr);
 
 	if (displayLineOffset > 0) {
 	    ComputeMissingMetric(textPtr, &info, THRESHOLD_LINE_OFFSET, displayLineOffset);
-	    info.numDispLines -= info.displayLineNo;
 
 	    while (1) {
 		const TkTextDispLineEntry *last;
 
+		info.numDispLines -= info.displayLineNo;
 		if ((int) info.numDispLines >= displayLineOffset) {
 		    last = info.entry + displayLineOffset;
 		    byteOffset = last->byteOffset;
 		    break;
 		}

Index: generic/tkTextIndex.c
==================================================================
--- generic/tkTextIndex.c
+++ generic/tkTextIndex.c
@@ -2943,11 +2943,23 @@
 
 	    forward = (count < 0) == (*string == '-');
 	    count = abs(count);
 
 	    if (forward) {
+		TkTextIndex indexPtr2 = *indexPtr;
+
+		/*
+		 * Check crossing of the end of text boundary. If crossed, adjust
+		 * xOffset so that the returned index will refer to the end of line.
+		 */
+
+		TkTextFindDisplayIndex(textPtr, &indexPtr2, count - 1, NULL);
 		TkTextFindDisplayIndex(textPtr, indexPtr, count, &xOffset);
+		if (!TkTextIndexCompare(&indexPtr2, indexPtr)) {
+		    TkTextIndexSetupToEndOfText(indexPtr, textPtr, textPtr->sharedTextPtr->tree);
+		    TkTextFindDisplayIndex(textPtr, indexPtr, 0, &xOffset);
+		}
 	    } else {
 		TkTextIndex indexPtr2 = *indexPtr;
 
 		/*
 		 * Check crossing of the start of text boundary. If crossed, adjust

Index: tests/textMark.test
==================================================================
--- tests/textMark.test
+++ tests/textMark.test
@@ -202,11 +202,11 @@
   focus -force .p
   event generate .p <<NextLine>>  ; # shall not error out
   set res [.p index insert]
 } -cleanup {
   destroy .p
-} -result {1.2}
+} -result {1.9}
 
 test textMark-7.1 {MarkFindNext - invalid mark name} -body {
     .t mark next bogus
 } -returnCodes error -result {bad text index "bogus"}
 test textMark-7.2 {MarkFindNext - marks at same location} -body {