【Power Apps】リッチテキストエディタに入力した画像・テキストをそのままTeamsに投稿する方法

MicrosoftTeams.PostMessageToConversation(
    "User", 
    "Channel", 
    ParseJSON(JSON({
            recipient:
                {
                    groupId: "groupId", 
                    channelId: "channelId"
                },
            messageBody: RichTextEditor1.HtmlText,
            subject: "件名"
        }
    ))
)

    {Html:MatchAll(RichTextEditor1.HtmlText, "<img.+?src=""data:(?<contentType>.+?);base64,(?<contentBytes>.+?)"" />")},    
    ClearCollect(
        ColPostText,
            {
                recipient:
                    {
                        groupId: "groupId", 
                        channelId: "channelId"
                    },
                messageBody: RichTextEditor1.HtmlText,
                subject: "件名",
                hostedContents:
                    ShowColumns(
                        AddColumns(
                            Html,
                            "@microsoft.graph.temporaryId",
                            Text(StartMatch)
                        ),
                        "contentBytes","contentType","@microsoft.graph.temporaryId"
                    )
            }
    );
    ForAll(
        Html As html,
        UpdateIf(
            ColPostText, true,
            {messageBody:Substitute(messageBody, html.FullMatch, "<img src=""../hostedContents/" & html.StartMatch & "/$value"">")}
        )
    );

    MicrosoftTeams.PostMessageToConversation(
        "User", 
        "Channel", 
        ParseJSON(JSON(First(ColPostText)))
    )
)