diff --git a/Sources/Runestone/Library/UITextInput+Helpers.swift b/Sources/Runestone/Library/UITextInput+Helpers.swift
index db115d56c..60b911840 100644
--- a/Sources/Runestone/Library/UITextInput+Helpers.swift
+++ b/Sources/Runestone/Library/UITextInput+Helpers.swift
@@ -6,7 +6,7 @@ import UIKit
 extension UITextInput where Self: NSObject {
     var sbs_textSelectionDisplayInteraction: UITextSelectionDisplayInteraction? {
         let interactionAssistantKey = "int" + "ssAnoitcare".reversed() + "istant"
-        let selectionViewManagerKey = "les_".reversed() + "ection" + "reganaMweiV".reversed()
+        let selectionViewManagerKey: String = "les_".reversed() + "ection" + "reganaMweiV".reversed()
         guard responds(to: Selector(interactionAssistantKey)) else {
             return nil
         }
diff --git a/Sources/Runestone/TextView/Navigation/TextLocation.swift b/Sources/Runestone/TextView/Navigation/TextLocation.swift
index df587505c..f70a762a0 100644
--- a/Sources/Runestone/TextView/Navigation/TextLocation.swift
+++ b/Sources/Runestone/TextView/Navigation/TextLocation.swift
@@ -7,6 +7,12 @@ public struct TextLocation: Hashable, Equatable {
     /// Column in the line.
     public let column: Int
 
+    /// Initializes TextLocation from the given line and column
+    public init (lineNumber: Int, column: Int) {
+        self.lineNumber = lineNumber
+        self.column = column
+    }
+
     init(_ linePosition: LinePosition) {
         self.lineNumber = linePosition.row
         self.column = linePosition.column
diff --git a/Sources/Runestone/TextView/SyntaxHighlighting/Internal/TreeSitter/TreeSitterInternalLanguageMode.swift b/Sources/Runestone/TextView/SyntaxHighlighting/Internal/TreeSitter/TreeSitterInternalLanguageMode.swift
index aa2e44677..d089d7682 100644
--- a/Sources/Runestone/TextView/SyntaxHighlighting/Internal/TreeSitter/TreeSitterInternalLanguageMode.swift
+++ b/Sources/Runestone/TextView/SyntaxHighlighting/Internal/TreeSitter/TreeSitterInternalLanguageMode.swift
@@ -16,6 +16,7 @@ final class TreeSitterInternalLanguageMode: InternalLanguageMode {
     private let lineManager: LineManager
     private let rootLanguageLayer: TreeSitterLanguageLayer
     private let operationQueue = OperationQueue()
+    private let parseLock = NSLock()
 
     init(language: TreeSitterInternalLanguage, languageProvider: TreeSitterLanguageProvider?, stringView: StringView, lineManager: LineManager) {
         self.stringView = stringView
@@ -37,7 +38,9 @@ final class TreeSitterInternalLanguageMode: InternalLanguageMode {
     }
 
     func parse(_ text: NSString) {
-        rootLanguageLayer.parse(text)
+        parseLock.withLock {
+            rootLanguageLayer.parse(text)
+        }
     }
 
     func parse(_ text: NSString, completion: @escaping ((Bool) -> Void)) {