Is there a brush tool to modify specific parts of a photo (like windows)?

Not currently in the traditional sense. AutoHDR has an AutoFill tool and an AutoRemove tool that let you mask regions of the image to add or remove items. We don't currently have a Photoshop-style brush for adjusting lightness, contrast, or color on specific areas.

Request the feature

If you'd like a brush tool, submit a request at autohdr.canny.io.