diff --git a/resources/META-INF/plugin.xml b/resources/META-INF/plugin.xml
index 7cccd40..c9f1dc2 100644
--- a/resources/META-INF/plugin.xml
+++ b/resources/META-INF/plugin.xml
@@ -7,6 +7,7 @@
     <h2>version 0.0.8</h2>
     <p>Features</p>
     <ul>
+        <li>improve detecting extras [#39] </li>
         <li>improve showing popup [#38] </li>
         <li>improve handling invalid interpreter [#37] </li>
     </ul>
diff --git a/src/com/koxudaxi/poetry/PoetryExtrasLineMarkerContributor.kt b/src/com/koxudaxi/poetry/PoetryExtrasLineMarkerContributor.kt
index 7484721..cee5f89 100644
--- a/src/com/koxudaxi/poetry/PoetryExtrasLineMarkerContributor.kt
+++ b/src/com/koxudaxi/poetry/PoetryExtrasLineMarkerContributor.kt
@@ -5,9 +5,7 @@ import com.intellij.icons.AllIcons.Actions.Install
 import com.intellij.openapi.actionSystem.ActionManager
 import com.intellij.psi.PsiElement
 import com.jetbrains.python.sdk.pythonSdk
-import org.toml.lang.psi.TomlKey
-import org.toml.lang.psi.TomlKeyValue
-import org.toml.lang.psi.TomlTable
+import org.toml.lang.psi.*
 
 object PoetryExtrasLineMarkerContributor : RunLineMarkerContributor() {
     override fun getInfo(element: PsiElement): Info? {
@@ -17,7 +15,9 @@ object PoetryExtrasLineMarkerContributor : RunLineMarkerContributor() {
         val keyValue = element.parent as? TomlKeyValue ?: return null
         val names = (keyValue.parent as? TomlTable)?.header?.names ?: return null
         if (names.joinToString(".") { it.text } != "tool.poetry.extras") return null
-        if (keyValue.key.text == null || keyValue.value?.text == null) return null
+        if (keyValue.key.text == null) return null
+        val value = keyValue.value as? TomlArray ?: return null
+        if (value.elements.isEmpty() || value.elements.any { it !is TomlLiteral || it.textLength < 3}) return null
         val action =ActionManager.getInstance().getAction(PoetryInstallExtras.actionID)
         return Info(Install, { parameter ->  "Install " + ((parameter as? TomlKey)?.text ?: "extra")}, arrayOf(action))
     }