diff --git a/README.md b/README.md
index 7c2859f..3a3b54e 100644
--- a/README.md
+++ b/README.md
@@ -78,6 +78,7 @@ make it work with JUnit 5. Feel free to use the code (in package ```de.platon42.
 - Bugfix: Missing REPT and ENDR assembler directives added.
 - Cosmetics: Changed or added some icons at various places.
 - Performance: Reference search for global labels and symbols now uses stub index.
+- Compatibility: Restored compatibility with IDEs versions < 2021.1.
 
 ### V0.2 (27-Jul-21)
 
diff --git a/build.gradle b/build.gradle
index a56db23..d3f1a02 100644
--- a/build.gradle
+++ b/build.gradle
@@ -44,6 +44,16 @@ intellij {
 //    setPlugins(["com.intellij.java"])
 }
 
+runPluginVerifier {
+    ideVersions = ["IC-193.5662.53", "IC-211.7628.21", // 2019.3.1 - 2021.1.3
+                   "CL-193.5233.103", "CL-193.7288.25", // 2019.3
+                   "CL-201.6668.126", "CL-201.8743.17", // 2020.1
+                   "CL-202.6397.106", "CL-202.8194.17", // 2020.2
+                   "CL-203.5981.166", "CL-203.8084.11", // 2020.3
+                   "CL-211.6693.114", "CL-211.7628.27"] // 2021.1
+    downloadDir = System.getProperty("user.home") + "/.gradle/caches/modules-2/files-2.1/com.jetbrains.intellij.idea"
+}
+
 patchPluginXml {
     setChangeNotes("""
   <h4>V0.3 (unreleased)</h4>
@@ -55,6 +65,7 @@ patchPluginXml {
       <li>Bugfix: Missing REPT and ENDR assembler directives added.
       <li>Cosmetics: Changed or added some icons at various places.
       <li>Performance: Reference search for global labels and symbols now uses stub index.
+      <li>Compatibility: Restored compatibility with IDEs versions < 2021.1.
     </ul>
   <h4>V0.2 (27-Jul-21)</h4>
     <ul>
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/M68kIcons.kt b/src/main/java/de/platon42/intellij/plugins/m68k/M68kIcons.kt
index 90def27..62097a5 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/M68kIcons.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/M68kIcons.kt
@@ -9,4 +9,6 @@ object M68kIcons {
     val GLOBAL_LABEL = AllIcons.Nodes.Method
     val SYMBOL_DEF = AllIcons.Nodes.ClassInitializer
     val MACRO_DEF = AllIcons.Nodes.MultipleTypeDefinitions
+    val REGISTER = AllIcons.Nodes.DataTables // AllIcons.Nodes.Record only available starting from 2020.1
+    val MNEMONIC = AllIcons.Nodes.C_protected
 }
\ No newline at end of file
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/asm/M68kMnemonicCompletionContributor.kt b/src/main/java/de/platon42/intellij/plugins/m68k/asm/M68kMnemonicCompletionContributor.kt
index e5a7f30..7704e71 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/asm/M68kMnemonicCompletionContributor.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/asm/M68kMnemonicCompletionContributor.kt
@@ -2,16 +2,16 @@ package de.platon42.intellij.plugins.m68k.asm
 
 import com.intellij.codeInsight.completion.*
 import com.intellij.codeInsight.lookup.LookupElementBuilder
-import com.intellij.icons.AllIcons
 import com.intellij.patterns.PlatformPatterns
 import com.intellij.util.ProcessingContext
+import de.platon42.intellij.plugins.m68k.M68kIcons
 import de.platon42.intellij.plugins.m68k.psi.M68kTypes
 
 class M68kMnemonicCompletionContributor : CompletionContributor() {
 
     companion object {
         val MNEMONICS = M68kIsa.mnemonics
-            .map { PrioritizedLookupElement.withPriority(LookupElementBuilder.create(it).withIcon(AllIcons.Nodes.Protected), 10.0) }
+            .map { PrioritizedLookupElement.withPriority(LookupElementBuilder.create(it).withIcon(M68kIcons.MNEMONIC), 10.0) }
     }
 
     init {
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kChooseByNameContributor.kt b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kChooseByNameContributor.kt
index 7b33a0c..2a0a5b2 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kChooseByNameContributor.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kChooseByNameContributor.kt
@@ -1,8 +1,7 @@
 package de.platon42.intellij.plugins.m68k.refs
 
-import com.intellij.navigation.ChooseByNameContributorEx2
+import com.intellij.navigation.ChooseByNameContributorEx
 import com.intellij.navigation.NavigationItem
-import com.intellij.openapi.project.Project
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.stubs.StubIndex
 import com.intellij.util.Processor
@@ -13,17 +12,17 @@ import de.platon42.intellij.plugins.m68k.psi.M68kSymbolDefinition
 import de.platon42.intellij.plugins.m68k.stubs.M68kGlobalLabelStubIndex
 import de.platon42.intellij.plugins.m68k.stubs.M68kSymbolDefinitionStubIndex
 
-class M68kChooseByNameContributor : ChooseByNameContributorEx2 {
+class M68kChooseByNameContributor : ChooseByNameContributorEx {
 
-    override fun processNames(processor: Processor<in String>, parameters: FindSymbolParameters) {
-        processNames(processor, parameters.searchScope, parameters.idFilter)
-    }
+//    override fun processNames(processor: Processor<in String>, parameters: FindSymbolParameters) {
+//        processNames(processor, parameters.searchScope, parameters.idFilter)
+//    }
 
-    override fun getItemsByName(name: String, pattern: String, project: Project, includeNonProjectItems: Boolean): Array<NavigationItem> {
-        val result: MutableList<NavigationItem> = ArrayList()
-        processElementsWithName(name, result::add, FindSymbolParameters.wrap(pattern, project, includeNonProjectItems))
-        return result.toTypedArray()
-    }
+//    override fun getItemsByName(name: String, pattern: String, project: Project, includeNonProjectItems: Boolean): Array<NavigationItem> {
+//        val result: MutableList<NavigationItem> = ArrayList()
+//        processElementsWithName(name, result::add, FindSymbolParameters.wrap(pattern, project, includeNonProjectItems))
+//        return result.toTypedArray()
+//    }
 
     override fun processNames(processor: Processor<in String>, scope: GlobalSearchScope, filter: IdFilter?) {
         StubIndex.getInstance().processAllKeys(M68kGlobalLabelStubIndex.KEY, processor, scope, filter)
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
index 7af34bb..174aec5 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
@@ -3,9 +3,9 @@ package de.platon42.intellij.plugins.m68k.refs
 import com.intellij.codeInsight.completion.*
 import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.lookup.LookupElementBuilder
-import com.intellij.icons.AllIcons
 import com.intellij.patterns.PlatformPatterns
 import com.intellij.util.ProcessingContext
+import de.platon42.intellij.plugins.m68k.M68kIcons
 import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
 import de.platon42.intellij.plugins.m68k.psi.M68kTypes
 
@@ -18,7 +18,7 @@ class M68kGlobalLabelSymbolCompletionContributor : CompletionContributor() {
                 "a0", "a1", "a2", "a3", "a4", "a5", "a6", "sp",
                 "pc"
             )
-                .map { PrioritizedLookupElement.withPriority(LookupElementBuilder.create(it).withIcon(AllIcons.Nodes.Record).withBoldness(true), 2.0) }
+                .map { PrioritizedLookupElement.withPriority(LookupElementBuilder.create(it).withIcon(M68kIcons.REGISTER).withBoldness(true), 2.0) }
     }
 
     init {
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
index c85507f..461f911 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
@@ -4,7 +4,6 @@ import com.intellij.ide.structureView.StructureViewTreeElement
 import com.intellij.ide.util.treeView.smartTree.TreeElement
 import com.intellij.navigation.ItemPresentation
 import com.intellij.psi.NavigatablePsiElement
-import com.intellij.refactoring.suggested.startOffset
 import de.platon42.intellij.plugins.m68k.psi.M68kFile
 import de.platon42.intellij.plugins.m68k.psi.M68kGlobalLabel
 import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
@@ -19,9 +18,9 @@ class M68kStructureViewElement(private val myElement: NavigatablePsiElement) : S
         return when (myElement) {
             is M68kFile -> {
                 listOf(
-                    M68kLookupUtil.findAllSymbolDefinitions(myElement).sortedBy { it.startOffset },
-                    M68kLookupUtil.findAllMacroDefinitions(myElement).sortedBy { it.startOffset },
-                    M68kLookupUtil.findAllGlobalLabels(myElement).sortedBy { it.startOffset },
+                    M68kLookupUtil.findAllSymbolDefinitions(myElement).sortedBy { it.textRange.startOffset },
+                    M68kLookupUtil.findAllMacroDefinitions(myElement).sortedBy { it.textRange.startOffset },
+                    M68kLookupUtil.findAllGlobalLabels(myElement).sortedBy { it.textRange.startOffset },
 //                    M68kLookupUtil.findAllSymbolDefinitions(myElement).sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.name!! }),
 //                    M68kLookupUtil.findAllGlobalLabels(myElement).sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.name!! })
                 )