add a button on jellyfin headband

[Anatole]

in my json file I have this, how do I add a button?


{
"includeCorsCredentials": false,
"multiserver": false,
"themes": [
{
"name": "Apple TV",
"id": "appletv",
"color": "#bcbcbc"
}, {
"name": "Blue Radiance",
"id": "blueradiance",
"color": "#011432"
}, {
"name": "Dark",
"id": "dark",
"color": "#202020",
"default": true
}, {
"name": "Light",
"id": "light",
"color": "#303030"
}, {
"name": "Purple Haze",
"id": "purplehaze",
"color": "#000420"
}, {
"name": "WMC",
"id": "wmc",
"color": "#0c2450"
}
],
"menuLinks": [],
"servers": [],
"plugins": [
"playAccessValidation/plugin",
"experimentalWarnings/plugin",
"htmlAudioPlayer/plugin",
"htmlVideoPlayer/plugin",
"photoPlayer/plugin",
"comicsPlayer/plugin",
"bookPlayer/plugin",
"youtubePlayer/plugin",
"backdropScreensaver/plugin",
"pdfPlayer/plugin",
"logoScreensaver/plugin",
"sessionPlayer/plugin",
"chromecastPlayer/plugin",
"syncPlay/plugin"
]
}