[Bug]: Error on startup every time in Rider #621
Description
Describe the bug
I've got a startup error, every time I've opened Rider's main window.
Rider's error popup is claiming this plugin is at fault.
Error is not blocking, just annoying spam.
To Reproduce
Open IDE to previous project
Error occurs.
Expected behavior
Error not thrown on startup
Material Theme Version
10.9.1
IDE
Rider
System Info
JetBrains Rider 2025.3.2
Build #RD-253.30387.148, built on January 29, 2026
Source revision: a1249671281c4
Licensed to REDACTED
Subscription is active until April 8, 2026.
Runtime version: 21.0.9+1-b1163.94 amd64 (JCEF 137.0.17)
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Toolkit: sun.awt.windows.WToolkit
Windows 11.0
.NET Core v9.0.11 x64 (Server GC)
GC: G1 Young Generation, G1 Concurrent GC, G1 Old Generation
Memory: 5120M
Cores: 16
Registry:
ide.balloon.shadow.size=0
editor.focus.mode.color.light=415967
editor.focus.mode.color.dark=415967
ide.new.editor.tabs.vertical.borders=true
new.search.everywhere.font.size.delta=4
ide.animate.toolwindows=true
ide.experimental.ui=true
ide.editor.tab.selection.animation=true
ide.colorful.toolbar.gradient.radius=2000
llm.selector.config.refresh.interval=10
llm.chat.agent.codex.install.acp.server.version=0.0.23
llm.show.ai.promotion.window.on.start=false
llm.chat.agent.codex.install.codex.version=0.98.0
llm.rules.refresh.interval=10
Non-Bundled Plugins:
com.intellij.qt (253.28294.337)
com.intellij.resharper.HeapAllocationsViewer (2025.3.0)
org.toml.lang (253.28294.334)
com.intellij.plugins.macoskeymap (252.16512.17)
Subversion (253.30387.193)
ru.adelf.idea.dotenv (253.30387.193)
com.intellij.copyright (253.28294.325)
org.jetbrains.junie (253.620.53)
it.czerwinski.ide.plugins.valve (1.1.6)
nl.bryanderidder.regexrenamefiles (1.3.2)
String Manipulation (9.16.0)
com.intellij.plugins.riderkeymap (201.6251.22)
unreal-link (2025.3.0.1708)
Key Promoter X (2024.2.2)
com.github.camork.fileExpander (2.5)
com.intellij.ml.llm (253.30387.186)
net.seesharpsoft.intellij.plugins.csv (4.2.0)
com.chrisrm.idea.MaterialThemeUI (10.9.1)
intellij.vitejs (253.30387.193)
com.intellij.lang.qml (253.29346.45)
com.mallowigi (104.0.0)
mobi.hsz.idea.gitignore (4.5.7)
Jetbrains TeamCity Plugin (2025.11.207946)
com.jetbrains.sqlproj (0.1.12)
me.rafaelldi.aspire (1.9.5)
WGSL (0.0.37)
izhangzhihao.rainbow.brackets (2025.3.7)Logs/Screenshots
java.lang.Throwable: An editable copy of Default has not been initialized.
at com.intellij.openapi.diagnostic.Logger.error(Logger.java:375)
at com.intellij.openapi.editor.colors.impl.EditorColorsManagerImpl.getEditableDefaultScheme(EditorColorsManagerImpl.kt:409)
at com.intellij.openapi.editor.colors.impl.EditorColorsManagerImpl.getGlobalScheme(EditorColorsManagerImpl.kt:384)
at com.mallowigi.idea.tabs.painters.MTTabsPainter.getTabUnderlineColor(MTTabsPainter.kt:255)
at com.mallowigi.idea.tabs.painters.MTTabsPainter.paintUnderline(MTTabsPainter.kt:159)
at com.intellij.ui.tabs.impl.JBEditorTabsBorder.paintBorder(JBEditorTabsBorder.kt:121)
at com.intellij.ui.tabs.impl.JBTabsImpl.drawBorder(JBTabsImpl.kt:2331)
at com.intellij.openapi.fileEditor.impl.EditorTabs.paintChildren(EditorTabbedContainer.kt:613)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1133)
at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:964)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1133)
at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:964)
at com.intellij.openapi.fileEditor.impl.EditorsSplitters.paintChildren(EditorsSplitters.kt:269)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1133)
at java.desktop/javax.swing.JComponent.paintToOffscreen(JComponent.java:5319)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBufferedFPScales(RepaintManager.java:1741)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1650)
at java.desktop/javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1589)
at java.desktop/javax.swing.RepaintManager.paint(RepaintManager.java:1349)
at java.desktop/javax.swing.JComponent._paintImmediately(JComponent.java:5267)
at java.desktop/javax.swing.JComponent.paintImmediately(JComponent.java:5077)
at java.desktop/javax.swing.JComponent.paintImmediately(JComponent.java:5058)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:884)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:867)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:867)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:840)
at java.desktop/javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:786)
at java.desktop/javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1918)
at com.intellij.util.concurrency.ChildContext$runInChildContext$1.invoke(propagation.kt:167)
at com.intellij.util.concurrency.ChildContext$runInChildContext$1.invoke(propagation.kt:167)
at com.intellij.util.concurrency.ChildContext.runInChildContext(propagation.kt:173)
at com.intellij.util.concurrency.ChildContext.runInChildContext(propagation.kt:167)
at com.intellij.util.concurrency.ContextRunnable.lambda$run$0(ContextRunnable.java:26)
at com.intellij.concurrency.ThreadContext.resetThreadContext(threadContext.kt:294)
at com.intellij.util.concurrency.ContextRunnable.run(ContextRunnable.java:25)
at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:781)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:728)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:722)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:750)
at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.kt:664)
at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.kt:517)
at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$0$0$0$0(IdeEventQueue.kt:337)
at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:901)
at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$0$0$0(IdeEventQueue.kt:336)
at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$1(IdeEventQueue.kt:1065)
at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:109)
at com.intellij.ide.IdeEventQueueKt.performActivity(IdeEventQueue.kt:1065)
at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$0(IdeEventQueue.kt:331)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.kt:363)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:207)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:92)