Thanks for the focused markdown rendering update. I found one blocking issue before this can merge: the current markdown-it setup keeps the default image rule enabled, so chat content like ![tracker](https://example.com/pixel) will render a real <img> and trigger a third-party request when the session page opens. That is a privacy/security regression compared with plain-text rendering. Please disable markdown images (for example by starting from the zero preset or disabling the image rule explicitly) and add a regression test proving image markdown does not produce an <img> tag.