Jetbrains Junie fails to take a PNG screenshot due to the quality parameter

[amenk]

Description of the bug

It's basically caught in a loop, JPEG works.
I have auto allowed all MCP commands.

The attempt to take a full-page PNG screenshot failed due to an unsupported 'quality' parameter error.

LLM is GPT-5

Does this mean there is a problem in the MCP server?

Reproduction

Take a screenshot of the webpage

Expectation

Takes a screenshot

MCP configuration

Standard

Chrome DevTools MCP version

latest

Chrome version

Version 142.0.7444.175 (Official Build) (64-bit)

Coding agent version

Junie 252.487.87

Model version

GPT-5

Chat log

No response

Node version

24

Operating system

Linux

Extra checklist

• I want to provide a PR to fix this bug

[OrKoN]

Thanks for reporting. What is the chrome-devtools-mcp server version you use?

[amenk]

The latest, installed today, like 30 minutes before the issue

[OrKoN]

Thanks! The tool instructions tell the LLM that quality will be ignored for png but underlying Puppeteer implementation actually throws an error. Should be fixed with #589

[amenk]

Cool - thanks for the quick fix, will try tomorrow.

Do you know why Junie endlessly retries the same call in that case? But maybe that's more a question for jetbrains

[OrKoN]

Yeah, this is up to the model or the client. Technically it should not also generate "quality: 0" at all as it makes little sense to pass 0 quality (should be just omitted). Also, uid and and filePath should be omitted instead of being empty strings. That might be a bug in the client.