[Bug] Severe UI Lag and Input Delay in Gemini Chat/Agent - Pop!_OS 24.04 (COSMIC/Wayland)

[daniakabani]

Environment Details:

• OS: Pop!_OS 24.04 LTS (COSMIC Desktop)
• Windowing System: Wayland
• IDE: WebStorm 2025.3.4
• Plugin Version: 1.49.1-253
• JVM Flags: -Dawt.toolkit.name=WLToolkit, -Dsun.java2d.opengl=false

Description:
The Gemini Code Assist chat panel is virtually unusable due to extreme input lag. As I type into the prompt box, the delay between keystrokes and character appearance increases exponentially. After ~50 characters, the IDE frequently hangs or becomes unresponsive for several seconds.

Steps to Reproduce:

• Open Gemini Chat in WebStorm on COSMIC (Wayland).
• Type a multi-line prompt into the input box.
• Observe the frame rate drop and the "ghosting" of text input.

Expected Behavior:
Fluid, real-time text input regardless of prompt length.

Actual Behavior:
The JCEF-rendered text box fails to capture input focus correctly, leading to massive thread blocking on the UI thread.

Webstorm info:
WebStorm 2025.3.4
Build #WS-253.32098.39, built on March 17, 2026
Source revision: a1f2bc0e0d733
Runtime version: 21.0.10+7-b1163.110 amd64 (JCEF 137.0.17)
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Toolkit: sun.awt.wl.WLToolkit
Linux 6.18.7-76061807-generic
Pop!_OS 24.04 LTS; glibc: 2.39
GC: G1 Young Generation, G1 Concurrent GC, G1 Old Generation
Memory: 2048M
Cores: 16
Registry:
ide.balloon.shadow.size=0
debugger.new.tool.window.layout=true
ide.new.editor.tabs.vertical.borders=true
new.search.everywhere.font.size.delta=4
ide.experimental.ui=true
ide.editor.tab.selection.animation=true
ide.colorful.toolbar.gradient.radius=2000
idea.islands.color.gradient.enabled=true
llm.chat.agent.codex.install.codex.version=0.114.0
llm.chat.agent.codex.install.acp.server.version=0.0.31
eslint.additional.file.extensions=svelte
Non-Bundled Plugins:
some.awesome (1.16)
org.toml.lang (253.28294.334)
com.github.xepozz.robots_txt (2025.1.0)
Subversion (253.32098.60)
ru.adelf.idea.dotenv (253.31033.143)
org.jetbrains.plugins.stylus (253.28294.251)
org.jetbrains.plugins.go-template (253.28294.218)
org.jetbrains.junie (253.819.54)
com.google.tools.ij.aiplugin (1.49.1-253)
com.intellij.properties (253.28294.334)
de.docs_as_co.intellij.plugin.diagramsnet (0.2.6)
Docker (253.32098.40)
com.intellij.ml.llm (253.32098.66)
org.intellij.prisma (253.29346.45)
com.github.aleksandrsl.intellijbrowserslist (2.0.0)
com.chrisrm.idea.MaterialThemeUI (10.10.0)
com.haulmont.rcb (253.29346.45)
com.mallowigi (104.0.0)
zielu.gittoolbox (600.2.5+253)
mobi.hsz.idea.gitignore (4.5.7)
dev.nx.console (1.58.0)
Current Desktop: COSMIC

[ivanporty]

Thank you for the report @daniakabani. Do you use any custom IME, non-English language when you enter your prompts?