This is a simple Lektor plugin that creates a template filter to remove HTML tags from a string. The use it was created for was to do processing on HTML outputted from a Markdown content field. The Markdown is rendered into HTML, and this filter can turn that into simple text, which was then passed to the lektor-natural-language filters to get keywords, unsullied by things like <div> tags.
Example usage:
{{ this.body|striphtmltags }}
{% set var = '<p><strong>Hello</strong>World!</p>' %}
{{ var|striphtmltags }}
The last example will render as "Hello World!"