Currently on 8.7 ugly HTML is used for the title of Query filter fields, this text displays when you hover over the filter input field. So for example if you have an attribute named "Number" the title text is "<div style='text-align: left'>Number</div>" and this is displayed to the user when they hover their mouse over the input field.
You can change this to a set value for all the filter inputs in the Query by adding the following code to the Render Script for any Query.
$('.k-filtercell :input'). attr('title', 'Filter by text');
This will display "Filter by text" on all the filter input fields.