Disabling Chrome tab groups
Paste chrome://flags/#enable-tab-groups in address bar and Tab groups options, choose default and re-launch Chrome by tapping the option at bottom. Tested on Chrome version 85.0.4183.127 (if that doesn't work for you try disable option).
( If you type Chrome://flags, you will get a scary warning, ignore that, changing flag properties is harmless-you can always reset flags, if you wish)