Может помочь загрузить файл:
public CorePage UploadHack(string fileInputId, string contentType, string fileContent, string fileName, string angularScopeVar)
{
UploadFile(_filePath);
var uploadHack =
"(function(){" +
"function convert(base64){" +
"var raw = atob(base64);" +
"var arr = new Uint8Array(new ArrayBuffer(raw.length));" +
"for (var i = 0; i < raw.length; i++){" +
"arr[i] = raw.charCodeAt(i);" +
"}" +
"return arr; " +
"}" +
$"var file = new Blob([convert('{fileContent}')], {{'type':'{contentType}'}}); " +
$"file.name = '{fileName}'; " +
$"angular.element('#{fileInputId}').scope().{angularScopeVar} = file;" +
"})()";
Driver.ExecuteJavaScript(uploadHack);
return this;
}