Re-submitting filter form duplicates _x querystring arguments #1214
Description
Really nasty bug, caused by #1194 fix in 07e1635
Navigate to this page: https://github-to-sqlite.dogsheep.net/github/labels?_search=help&_sort=id
Click "Apply" to submit the form and the resulting URL is https://github-to-sqlite.dogsheep.net/github/labels?_search=help&_sort=id&_search=help&_sort=id
That's because the (truncated) HTML for the form looks like this:
... <input id="_search" type="search" name="_search" value="help">
...
<div class="select-wrapper small-screen-only">
<select name="_sort" id="sort_by">
<option value="">Sort...</option>
<option value="id" selected>Sort by id</option>
<option value="node_id">Sort by node_id</option>
...
</select>
</div>
...
<input type="hidden" name="_search" value="help">
<input type="hidden" name="_sort" value="id">
<input type="submit" value="Apply">