data-tooltip does not support multiline text / newline characters

[jiang3li4]

Describe the bug

The data-tooltip attribute used to create tooltips in Marimo does not support multiline content. Newline characters (including \n and the HTML entity ) are not rendered as line breaks inside the tooltip — the tooltip always displays as a single line regardless of the content.

Will you submit a PR?

• Yes

Environment

{
"marimo": "0.23.1",
"editable": false,
"location": "/home/vsc/marimo_notebooks/.pixi/envs/default/lib/python3.12/site-packages/marimo",
"OS": "Linux",
"OS Version": "5.14.0-687.42.1.el9_8.x86_64",
"Processor": "x86_64",
"Python Version": "3.12.13",
"Locale": "--",
"Binaries": {
"Browser": "152.0.7977.82",
"Node": "v26.3.0",
"uv": "0.11.4 (x86_64-unknown-linux-musl)"
},
"Dependencies": {
"click": "8.2.2",
"docutils": "0.22",
"itsdangerous": "2.2.0",
"jedi": "0.19.2",
"markdown": "3.8.2",
"narwhals": "2.0.1",
"packaging": "25.0",
"psutil": "5.9.8",
"pygments": "2.19.2",
"pymdown-extensions": "10.21.3",
"pyyaml": "6.0.2",
"starlette": "0.47.2",
"tomlkit": "0.13.3",
"typing-extensions": "4.15.0",
"uvicorn": "0.35.0",
"websockets": "15.0.1"
},
"Optional Dependencies": {
"altair": "5.5.0",
"anywidget": "0.11.0",
"duckdb": "0.10.2",
"loro": "1.13.1",
"mcp": "1.27.2",
"openai": "1.109.1",
"pandas": "2.3.1",
"polars": "1.41.2",
"pyarrow": "24.0.0",
"pytest": "8.4.1",
"ruff": "0.12.7",
"sqlglot": "27.20.0"
},
"Experimental Flags": {}
}

Code to reproduce

import marimo as mo

data = [
    {
        "row_id": mo.md('<div data-tooltip="This is row A&#10; info">row_a</div>'),
        "value": 42,
    },
    {
        "row_id": mo.md('<div data-tooltip="This is row B\n info">row_b</div>'),
        "value": 17,
    },
    {
        "row_id": mo.Html('<div data-tooltip="This is row C\n info">row_c</div>'),
        "value": 33,
    },
]

table = mo.ui.table(data=data)
table

[mscolnick]

thanks for flagging - we will look to fix (looks like someone has already contributed a PR)