Description of problem:

The terminal shows a minor strange looking scrollbar and padding in the terminal which doesn't match the terminal background color.

This is a minor visual issue which is more visible when the scrollbar is always visible and has down and up buttons. This means, this is much more visible on a Linux system then on MacOS (where the default settings shows the scrollbar only when the user scrolls).

See attached videos, its much more visible on "my" Chrome 89 (Fedora on 33) then on my Firefox 86 (also Fedora 33)

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce

1. Switch to developer perspective and add a Deployment to start a Pod
2. Select your deployment in topology and select the running Pod
3. On the Pod details page switch to the "Terminal" tab
4. Check the scrollbar, resize the window

Actual results:

1. The scrollbars jumps and there is a small gap below the scrollbar. This bottom padding looks strange (but it's not a css padding)

Expected results:

1. If required the scrollbar height could jump but the black padding below the scrollbar looks unnecessary and should not be shown.

Reproducibility (Always/Intermittent/Only Once):

Always (better on Linux)

Build Details:

1. Latest 4.8 console master (tested with 4c443747272cd262ebc0e8d35491a0363af3c02c)

Additional info:

Also appears on 4.7, not tested on 4.6. So this is not related to the xterm update from 3.12 to 4.10 (ODC-5547, PR 8260).