diff --git a/src/main/kotlin/com/github/lppedd/cc/CCExtensions.kt b/src/main/kotlin/com/github/lppedd/cc/CCExtensions.kt
index 714306ab..8209ea56 100644
--- a/src/main/kotlin/com/github/lppedd/cc/CCExtensions.kt
+++ b/src/main/kotlin/com/github/lppedd/cc/CCExtensions.kt
@@ -1,5 +1,6 @@
 package com.github.lppedd.cc
 
+import com.github.lppedd.cc.annotation.RequireEDT
 import com.intellij.codeInsight.AutoPopupController
 import com.intellij.codeInsight.completion.CompletionParameters
 import com.intellij.codeInsight.lookup.impl.LookupImpl
@@ -82,11 +83,13 @@ internal inline fun Editor.insertStringAtCaret(string: String) {
 internal inline fun Editor.getTemplateState(): TemplateState? =
   TemplateManagerImpl.getTemplateState(this)
 
+@RequireEDT
 internal fun Editor.getCurrentLineRange(): TextRange {
   val mainCaretLine = EditorUtil.calcCaretLineRange(this).first.line
   return document.getLineRange(mainCaretLine)
 }
 
+@RequireEDT
 internal fun Editor.getCurrentLine(): CharSequence {
   val (start, end) = getCurrentLineRange()
   return document.immutableCharSequence.subSequence(start, end)
diff --git a/src/main/kotlin/com/github/lppedd/cc/annotation/RequireEDT.kt b/src/main/kotlin/com/github/lppedd/cc/annotation/RequireEDT.kt
new file mode 100644
index 00000000..36fa9192
--- /dev/null
+++ b/src/main/kotlin/com/github/lppedd/cc/annotation/RequireEDT.kt
@@ -0,0 +1,9 @@
+package com.github.lppedd.cc.annotation
+
+/**
+ * @author Edoardo Luppi
+ */
+@Target(AnnotationTarget.FUNCTION)
+@Retention(AnnotationRetention.BINARY)
+@MustBeDocumented
+annotation class RequireEDT