You'll need to create a custom service type, that will allow you to show/hide the individual text boxes. You can find an example in the Azure DevOps Extension Tasks which I maintain.
You define custom service endpoint types in the vss-extension.json
along with your other extension points:
{
"id": "vsts-marketplace-endpoint-type",
"type": "ms.vss-endpoint.service-endpoint-type",
"targets": [
"ms.vss-endpoint.endpoint-types"
],
"properties": {
"name": "VstsMarketplacePublishing",
"displayName": "Visual Studio Marketplace",
"url": {
"displayName": "Marketplace URL",
"value": "https://marketplace.visualstudio.com",
"isVisible": "false"
},
"helpMarkDown": "Required permissions: <ul><li><b>Publish</b>: All accessible organisations, Marketplace (Publish)</li><li><b>Share</b>: All accessible organisations, Marketplace Publish</li><li><b>Install</b>: All accessible organisations or a specific organisation, Extensions (read and manage), Marketplace (acquire)</li><li><b>Query Version</b>: All accessible organisations, Marketplace (read)</li><li><b>Is Valid Extension</b>: All accessible organisations, Marketplace (read)</li></ul><br/><a href='https://www.visualstudio.com/docs/setup-admin/team-services/use-personal-access-tokens-to-authenticate'>More information</a>.",
"authenticationSchemes": [
{
"type": "ms.vss-endpoint.endpoint-auth-scheme-basic",
"inputDescriptors": [
{
"id": "username",
"name": "Username",
"description": "Username",
"inputMode": "textbox",
"isConfidential": false,
"validation": {
"isRequired": false,
"dataType": "string",
"maxLength": 300
},
"values": {
"inputId": "username",
"isDisabled": true,
"defaultValue": ""
}
},
{
"id": "password",
"name": "Personal access token",
"description": "Azure DevOps personal access token.",
"inputMode": "passwordbox",
"isConfidential": true,
"validation": {
"isRequired": true,
"dataType": "string",
"maxLength": 300
}
}
]
}
]
}
},
You may find other extensions that set or configure the authentication dialog on GitHub, there are quite a few. Useful docs are here in an old blog post.