diff --git a/internal/stringext/string.go b/internal/stringext/string.go
index 03456db93bc148f7c77e52da3c493c94fa79624f..8be28ccc2096c3d54b9f3106ed30d584503acdf4 100644
--- a/internal/stringext/string.go
+++ b/internal/stringext/string.go
@@ -1,6 +1,8 @@
 package stringext
 
 import (
+	"strings"
+
 	"golang.org/x/text/cases"
 	"golang.org/x/text/language"
 )
@@ -8,3 +10,13 @@ import (
 func Capitalize(text string) string {
 	return cases.Title(language.English, cases.Compact).String(text)
 }
+
+// NormalizeSpace normalizes whitespace in the given content string.
+// It replaces Windows-style line endings with Unix-style line endings,
+// converts tabs to four spaces, and trims leading and trailing whitespace.
+func NormalizeSpace(content string) string {
+	content = strings.ReplaceAll(content, "\r\n", "\n")
+	content = strings.ReplaceAll(content, "\t", "    ")
+	content = strings.TrimSpace(content)
+	return content
+}
diff --git a/internal/ui/chat/tools.go b/internal/ui/chat/tools.go
index 8aac1c1401fe299b24bd2cda81e18113bfd6176d..3ae403160b241eca6f5d74fb9841c2b10a7735b9 100644
--- a/internal/ui/chat/tools.go
+++ b/internal/ui/chat/tools.go
@@ -15,6 +15,7 @@ import (
 	"github.com/charmbracelet/crush/internal/diff"
 	"github.com/charmbracelet/crush/internal/fsext"
 	"github.com/charmbracelet/crush/internal/message"
+	"github.com/charmbracelet/crush/internal/stringext"
 	"github.com/charmbracelet/crush/internal/ui/anim"
 	"github.com/charmbracelet/crush/internal/ui/common"
 	"github.com/charmbracelet/crush/internal/ui/styles"
@@ -531,9 +532,7 @@ func toolHeader(sty *styles.Styles, status ToolStatus, name string, width int, n
 
 // toolOutputPlainContent renders plain text with optional expansion support.
 func toolOutputPlainContent(sty *styles.Styles, content string, width int, expanded bool) string {
-	content = strings.ReplaceAll(content, "\r\n", "\n")
-	content = strings.ReplaceAll(content, "\t", "    ")
-	content = strings.TrimSpace(content)
+	content = stringext.NormalizeSpace(content)
 	lines := strings.Split(content, "\n")
 
 	maxLines := responseContextHeight
@@ -566,8 +565,7 @@ func toolOutputPlainContent(sty *styles.Styles, content string, width int, expan
 
 // toolOutputCodeContent renders code with syntax highlighting and line numbers.
 func toolOutputCodeContent(sty *styles.Styles, path, content string, offset, width int, expanded bool) string {
-	content = strings.ReplaceAll(content, "\r\n", "\n")
-	content = strings.ReplaceAll(content, "\t", "    ")
+	content = stringext.NormalizeSpace(content)
 
 	lines := strings.Split(content, "\n")
 	maxLines := responseContextHeight
@@ -776,9 +774,7 @@ func roundedEnumerator(lPadding, width int) tree.Enumerator {
 
 // toolOutputMarkdownContent renders markdown content with optional truncation.
 func toolOutputMarkdownContent(sty *styles.Styles, content string, width int, expanded bool) string {
-	content = strings.ReplaceAll(content, "\r\n", "\n")
-	content = strings.ReplaceAll(content, "\t", "    ")
-	content = strings.TrimSpace(content)
+	content = stringext.NormalizeSpace(content)
 
 	// Cap width for readability.
 	if width > maxTextWidth {
diff --git a/internal/ui/list/highlight.go b/internal/ui/list/highlight.go
index fefe836d110b52496028d21071fffc5262189d92..631181db29ce5bc3a2087de30341342f0374b229 100644
--- a/internal/ui/list/highlight.go
+++ b/internal/ui/list/highlight.go
@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"charm.land/lipgloss/v2"
+	"github.com/charmbracelet/crush/internal/stringext"
 	uv "github.com/charmbracelet/ultraviolet"
 )
 
@@ -53,6 +54,8 @@ func Highlight(content string, area image.Rectangle, startLine, startCol, endLin
 // HighlightBuffer highlights a region of text within the given content and
 // region, returning a [uv.ScreenBuffer].
 func HighlightBuffer(content string, area image.Rectangle, startLine, startCol, endLine, endCol int, highlighter Highlighter) *uv.ScreenBuffer {
+	content = stringext.NormalizeSpace(content)
+
 	if startLine < 0 || startCol < 0 {
 		return nil
 	}