@drfreepony
You are currently using the ‘Global’ site-wide
Default filter. You can’t modify that.
What you need to do is go to Filters in the menu bar, and scroll down to Global Filters.
There, select the Copy and Customize. Change the name Default to whatever you would like, and click the ‘x’ on the semi-grimdark tag which will be in the Spoilered Tags section.
Click the Save Filter button, and then select it in the list of filters in the pop-up list of filters.
From that point on, you will be able to add or remove filtering on tags using the tags themselves on images, because you have your own personal ‘custom filter’.
If you have any questions or would like more help, please let me know.
