This is the seal between the actual glass pane (or the insulated glass unit) and the window sash (the outer frame that holds the glass). This is usually a butyl tape, silicone bead, or a structural glazing gasket. When this fails, you get or water dripping down the inside of the glass surface.
If you used painter's tape, peel it off immediately while the caulk is still wet. Pull the tape away at a 45-degree angle to keep the lines sharp. Do not touch the caulk while it cures. Most high-quality silicone sealants take 24 to 48 hours to cure completely before they can handle direct rain. 4. Pro-Tips for a Flawless Finish how to reseal a window fixed
Cut the tip of the caulk tube at a 45-degree angle. Puncture the inner seal. Insert the tube into the caulk gun. Hold the gun at a steady angle and pull it toward you, forcing caulk into the gap. Aim for a bead about ¼ inch thick. This is the seal between the actual glass
If you feel air or see light at the edges where the frame meets the wall, you can fix this with sealant or insulation. If you used painter's tape, peel it off