Hi FoeAndArrows! Thanks for the response. I turned off all my extensions, cleared cache, and redid everything in both Chrome and Firefox, but it still happened. But redoing the problem and troubleshooting it revealed what was happening. It's still odd that it happened and I'm not sure why it did, but I'll add it below just in case anyone has the same issue.
p.p1 {margin: 0.0px 0.0px 10.0px 0.0px; line-height: 18.0px; font: 16.0px Helvetica; color: #293437; -webkit-text-stroke: #293437}
span.s1 {font-kerning: none}
Basically, whenever I clicked on the Drawing Tool, the default color would reset to "HEX: (my email address)", instead of HEX #ff0000, (which is usually dictated by the color next to your Avatar at the bottom of the screen) , mine is usually Red (#ff0000). This was why whenever I drew a line using the freehand tool, it resulted in a semi-invisible black line, I guess because it was referencing a non-color. I looked at my avatar and noticed that the color box that's usually next to my name was missing. So I just went into my in-game settings, scrolled down to "Reset player video/avatar location" , changed the avatar size back to Regular, and the color appeared again. And sure enough, it fixed it! The weird thing about it was, it was showing a different email address from an old Roll20 account I had made, not the current email address that is linked to this account. Autofill is disabled for Chrome and Firefox. Either way the is problem solved, thanks!