Fog of War acting erratically & unusable

I've just uploaded a large 70px 56x40 3920x2800 map up to Roll20, created a new map page. Turned on fog of War in the page settings. Made a square visible. When I scroll, the visible area elongates following the cursor up and down left and right. When I zoom in and out, it changes shape, not staying consistent. If by some miracle I scroll/zoom long enough, I may see the original sized area I made visible. A week ago Fog of War (basic) was working fine. Existing maps created show correct visible areas. This only seems to happen with new maps I create now.

I've narrowed down the bug to a very specific set of circumstances where it occurs: (yes I tried clearing my cache, updating my browser, login out and in again, etc.) - If I copy an existing page where Fog of War is working and load a new map there, it still happens - If I create a new page with Fog of War already enabled, it still happens - If I create a new page and then turn on Fog of War, either from the settings or the tools, it still happens - BUT it only seems to be happening IF the very first shape I create with the newly activated Fog of War uses the Reveal Area tool. If I create that first shape using the Polygon Reveal tool, Fog of War works just fine. STEPS TO REPRODUCE: 1. Create a new map, with or without Fog of War active 2. Place map image 3. Select the Reveal Area tool 4. Use the tool to designate an area of visibility in the Fog of War, and activate Fog of War if not already active 5. Scroll and Zoom