A couple of items that need to be addressed with regards to the filter form.
[ ] While minor, it might be worth giving the form a name attribute such as name="filter-form"
[ ] While the group of checkboxes are inside a fieldset element, there is no legend. As such the group label is not associated with its fields.
[ ] The "Clear" function should be a button element or even an input of type="reset" as opposed to an anchor element
[ ] The heading for the overall form could be a bit more descriptive. Something like "Filter posts by Products & Technologies". If this is a bit to much copy, we can use this string as the value for an aria-label
A couple of items that need to be addressed with regards to the filter form.
name
attribute such asname="filter-form"
fieldset
element, there is no legend. As such the group label is not associated with its fields.button
element or even an input oftype="reset"
as opposed to an anchor elementaria-label
Something like: