altair tooltip images not rendering #6928
Description
Describe the bug
When I run the code below in a Jupyter notebook, I get images as tooltips. In marimo, I only see the URLs. I experience similar behavior with base64-encoded images.
Will you submit a PR?
- Yes
Environment
{
"marimo": "0.17.0",
"editable": false,
"location": "/opt/homebrew/Caskroom/miniforge/base/envs/rdkit_2025_09/lib/python3.11/site-packages/marimo",
"OS": "Darwin",
"OS Version": "24.6.0",
"Processor": "arm",
"Python Version": "3.11.13",
"Locale": "en_US",
"Binaries": {
"Browser": "141.0.7390.123",
"Node": "v22.17.0"
},
"Dependencies": {
"click": "8.2.1",
"docutils": "0.22.1",
"itsdangerous": "2.2.0",
"jedi": "0.19.2",
"markdown": "3.9",
"narwhals": "2.5.0",
"packaging": "25.0",
"psutil": "7.0.0",
"pygments": "2.19.2",
"pymdown-extensions": "10.16.1",
"pyyaml": "6.0.2",
"starlette": "0.48.0",
"tomlkit": "0.13.3",
"typing-extensions": "4.15.0",
"uvicorn": "0.35.0",
"websockets": "15.0.1"
},
"Optional Dependencies": {
"altair": "5.5.0",
"nbformat": "5.10.4",
"pandas": "2.3.2",
"pyarrow": "17.0.0",
"loro": "1.6.0",
"ruff": "0.13.1"
},
"Experimental Flags": {}
}