Summary

Title Filter starting with "-" in "Content by Label" doesn't work properly.

Description

Filters starting with a dash in Content by Label don't workly. After applying filters, Preview doesn't show the pages where the title starts with a dash sign.

Steps to reproduce

1. Create a few pages with titles starting with a dash such as - Title 1, - Title 2, - Title 3.
2. Assign these newly created pages some label, for example, test
3. Now go to an already existing page and add a Content by Label macro.
4. Add a filter with Label test and another filter with Title - Title.
5. Click on Preview and then save. Pages with titles such as - Title 1 will not be shown.
6. Now Edit the macro and you will see the dash sign from the Title filter is gone.