Extension Gray/Blank Screen Issue - Consolidated Investigation & Current Status

[MuriloFP]

TLDR

If you’re seeing the gray screen bug, you don’t need to read the whole issue. Just run VS Code like this: code --verbose.

When the screen goes gray, copy the output from that terminal and any errors from Developer Tools (Help > Toggle Developer Tools > Console tab).

Post those logs in the issue, along with your OS, VS Code version, Roo extension version, and what you were doing right before it happened.

Summary

This issue consolidates all findings from #2270 regarding the persistent "gray/blank screen" problem affecting multiple users across different platforms. After 3+ months of investigation and 35+ comments, this summary provides a clean overview of what we know and what still needs to be done.

Problem Description

Users experience a complete UI failure where the Roo Code extension window becomes gray/blank, requiring VS Code restart. The issue:

• Affects Windows, macOS, and Linux users
• Occurs during long-running tasks or with multiple VS Code instances
• Sometimes allows background task continuation despite UI failure
• Can result in permanent loss of task history access
• Frequency: Multiple times per day for affected users
• Has been reported since April 2025, still unresolved

User Reports Summary

• @ianlintner: "Running 4 instances of cursor, all gray screen of death at the same time on Mac. Deal with it half a dozen times during the day"
• @appscaptain: "Up at 57k context window, needs to run terminal command, whole interface becomes blank during thinking"
• @shanemmattner: "Gray screens every 1-2 hours, Roo is close to unusable"
• @NightOwlCoder: "Can't find good repro steps, it just happens"
• @Promethean-Pty-Ltd: "Getting greyed-out window several times a day... sometimes can no longer access Task and chat history"

Technical Findings

Identified Issues

1. Task History Storage: The taskHistory array is stored in VS Code's globalState

   • Triggers warnings: "large extension state detected (1.4MB+)"
   • Entire array propagated to webview on every state update
   • Sequential scanning of thousands of HistoryItem objects

2. Memory Management:

   • Large task strings in HistoryItem objects
   • No pruning mechanism for historical data
   • Inefficient state synchronization

3. Potential Causes:

   • Race conditions with multiple VS Code instances
   • WebView context retention issues
   • Memory pressure from large state transfers

Reproduction Attempts

No consistent reproduction steps found despite extensive efforts.

Common patterns observed:

• Long-running tasks with high token usage (50k+ contexts)
• Multiple VS Code instances with Roo active
• Frequent terminal command approvals
• Extended usage periods (1-2 hours)
• Heavy usage with advanced models (DeepSeek R1, Gemini 2.5 Pro)

Current Workarounds

Users have reported these temporary solutions:

1. Increase VS Code heap size: code --max-memory=8192
2. Regularly close completed tasks
3. Restart VS Code when issue occurs
4. Limit to single VS Code instance
5. Close all editor windows for long-running tasks

Investigation Status

Attempted Solutions

• PR 3 of 3: scalability fix: refactor task history persistence to use file-based storage #3785: Proposed file-based storage migration (status unknown)
• PR Add a JSONL implementation with benchmark and findings #2868: JSONL implementation (closed)
• Various debugging attempts with code --verbose

What We Still Need

1. Reliable Reproduction Steps: Critical for debugging
2. Stack Traces: When gray screen occurs with code --verbose
3. Memory Profiling: During the failure state
4. Error Boundaries: To capture and report failures

Next Steps

1. Find Reliable Reproduction

   • Need users to run code --verbose and capture logs
   • Document exact steps when issue occurs
   • Capture memory usage patterns

2. Implement Diagnostics

   • Add error boundaries to catch UI failures
   • Implement telemetry for state size monitoring
   • Add debug logging for state operations

3. Develop Fix Strategy

   • Based on reproduction findings
   • May require fundamental architecture changes
   • Need to address both storage and UI resilience

How to Help

If you experience this issue:

1. Launch VS Code with: code --verbose
2. Note exact actions before gray screen
3. Capture console output
4. Report VS Code version, OS, and extension version
5. Check Developer Tools console for errors

Related Issues

• Original issue: Extension goes "blank" / Grey Screen #2270
• Related: Grey/blank Screen or Crashing Related #2391 (closed)

---

This is a summary of the ongoing investigation. The original issue (#2270) contains the full discussion history.

[complyue]

I suspect it's due to extremely long conversation, not necessarily visible length, invisible tool call logs should count.

I encountered the gray/blank panel after tell Roo to investigate into checked out llvm-project dir, which is a sufficiently large codebase, and Roo has to scan a big part of it to gain the knowledge it needs.

Reopened vscode and reloaded that conversation after it goes blank/grey, it hogs ~300% CPU for quite a while though the UI didn't go blank/grey before I force quit vscode after quite a while.

Overall, maybe just waste enough tokens to populate sufficient long conversation can reproduce it. I see Cursor would truncate slightly longer conversations on the go, the user has to click "see more" on the top to see older conversation history, that may be an effective strategy to prevent such blank/grey panel or CPU hogging behavior.

[x123]

Before the gray screen, this is indeed in a very long running task/conversation which gray screens often.

[26115:0722/125741.511612:INFO:CONSOLE(35)] "%cTRACE color: #888 [secrets] decrypted secret for key: secret://{"extensionId":"rooveterinaryinc.roo-cline","key":"roo_cline_config_api_config"}", source: vscode-file://vscode-app/nix/store/fisgzfjwmj1sk5fvxcbhkwrm8hwiqqb6-vscode-1.102.1/Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js (35)
[26115:0722/125741.511678:INFO:CONSOLE(35)] "%cTRACE color: #888 [mainThreadSecretState] Password found for:  rooveterinaryinc.roo-cline roo_cline_config_api_config", source: vscode-file://vscode-app/nix/store/fisgzfjwmj1sk5fvxcbhkwrm8hwiqqb6-vscode-1.102.1/Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js (35)

<--- Last few GCs --->

[26125:0x11800c80000]  1106723 ms: Scavenge (reduce) (interleaved) 3904.7 (3961.7) -> 3904.9 (3961.7) MB, pooled: 32 MB, 157.96 / 0.00 ms  (average mu = 0.871, current mu = 0.736) allocation failure;
[26125:0x11800c80000]  1106891 ms: Scavenge (reduce) (interleaved) 3904.9 (3961.7) -> 3905.6 (3961.7) MB, pooled: 32 MB, 168.04 / 0.00 ms  (average mu = 0.871, current mu = 0.736) allocation failure;


<--- JS stacktrace --->

[26125:0722/125741.933191:ERROR:v8_initializer.cc(825)] V8 javascript OOM (MarkCompactCollector: young object promotion failed).
[0722/125742.117176:ERROR:directory_reader_posix.cc(43)] opendir /Users/REDACTED/Library/Application Support/Code/Crashpad/attachments/f39573a5-b4bb-48f2-88ef-7092004fd871: No such file or directory (2)

[daubman]

RE:

Increase VS Code heap size: code --max-memory=8192

I get this error when attempting to use this:

$ code --max-memory=8192
Warning: 'max-memory' is not in the list of known options, but still passed to Electron/Chromium.

And according to this, that option was removed back in 2023 - so why is it listed as potentially helping?

• microsoft/vscode@6d5b854
• via: Warning: 'max-memory' is not in the list of known options, but still passed to Electron/Chromium. microsoft/vscode#182429 (comment)