System Information
Operating system: Windows-10-10.0.22000-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 2060 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 512.15

Blender Version
Broken: version: 3.2.0 Alpha, branch: master, commit date: 2022-04-05 23:33, hash: `rB931ae424b9ef, current Stable Releases, Daily, LTS, 2.81a (and many more I haven't tested)
Worked: none that I've tested

Short description of error
The Glare node doesn't change the Alpha Channel, which results in not saving the Bloom to the file if it is on a transparent area

This seems to also affect Eevee's Bloom rendering settings

Exact steps for others to reproduce the error
1 Create a scene with an glowing object and enable transparent rendering
2 Enable Composting nodes and add a Glare node set to Fog Glow
3 Render image to a file, it is still visible like expected inside Composting

Expected Result: Glare Node changes Alpha Chanel to make Bloom visible on transparent areas
Actual Result: Bloom is fully invisible on transparent areas