### Apache Airflow version

2.3.3 (latest released)

### What happened

An URL I saved in the past, `https://astronomer.astronomer.run/dx4o2568/home?tags=test`,  has the tag field in the query parameter though I was not aware of this. When I clicked on the URL, I was confused because I did not see any DAGs when I should have a bunch.

After closer inspection, I realized that the URL has the tag field in the query parameter but then noticed that the tag box in the Airflow UI wasn't properly populated.

![screen_shot_2022-07-12_at_8 11 07_am](https://user-images.githubusercontent.com/5952735/182496710-601b4a98-aacb-4482-bb9f-bb3fdf9e265f.png)


### What you think should happen instead

When I clicked on the URL, the tag box should have been populated with the strings in the URL.

### How to reproduce

Start an Airflow deployment with some DAGs and add the tag query parameter. More specifically, it has to be a tag that is not used by any DAG.

### Operating System

N/A

### Versions of Apache Airflow Providers

_No response_

### Deployment

Astronomer

### Deployment details

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""
    Some endpoints are called by javascript,
    returning json will allow us to more elegantly handle side-effects in-page
    """
    if request.headers.get("Accept") == "application/json":
        if status == "error" and status_code == 200:
            status_code = 500
        return Response(response=msg, status=status_code, mimetype="application/json")
    else:
        if status:
            flash(msg, status)
        else:
            flash(msg)
        return redirect(origin)
def not_found(error):
    """Show Not Found on screen for any error in the Webserver"""
    return (
        render_template(
            "airflow/error.html",
            hostname=get_hostname()
            if conf.getboolean("webserver", "EXPOSE_HOSTNAME", fallback=True)
            else "redact",
            status_code=404,
            error_message="Page cannot be found.",
        ),
        404,
    )
def method_not_allowed(error):