Thanks for your contribution.
As I mentioned on the issue prior to you posting this to Utopian, this is not a bug. I have further confirmed this with the project owner following this report.
In the scenario where a user enters the application and enters a username and private posting key and the private posting key is incorrect the validation is not done at login and instead done upon the actual action which requires the private posting key.
For example, I could enter the username kr-nalid and essentially view the application as you, but when I try to post as you I won't be able to because I don't know your private posting key. This is not a security concern because a user cannot do anything on a user's accounts without a private posting key.
The following diagram should explain this further, Note: I have oversimplified this, therefore, it isn't 100% accurate, but you will get the idea
In a lot of other applications you will validation of keys at the launch of the application through a sign in as seen in the image above, SteemApp instead takes a different approach and does the validation at the action as seen in the above image. This allows a user to get an experience within the application without needing to actually have your key to hand. Of course, this does create a slight UX issue and may be confusing, however, I think by removing the password field and only requiring the permission on actions (such as we saw Android implement in 6.0) it will help improve this for the user.
Again, I would like to note there is nothing to worry about when using this application and all users of the application are safe when using it.
Separate to that, it's great to see that you're adding your issues to GitHub, however, please take note of comments, this issue would have been best left until the project owner was able to respond. You also score higher points in the event the project owner acknowledges the issue.
Your title could have been improved by actually mentioning the issue at hand.
Your video was to the point and glad to see you made an attempt to hide your keys, I was initially worried that would be missed.
Once again, thanks for your contribution and look forward to your contibutions in the future.
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