🔹 Card-mod - Add css styles to any lovelace card

I gonna ask some probably silly questions (sorry for broken English).

I have HA on RPi 3 (docker).
My HA setup includes 3 dashboards (for HA itself, for testing things, for testing card-mod), each dashboard includes lots (~10…20) of views.
This is all edited in UI, not in yaml files (I know nothing about yaml-mode, it is in my plans).
And I use an old card-mod syntax in most cases (99%).

Every time when I work with Inspector (Chrome, Win10x64) with views with card-mod, I observe a high CPU load on my PC (~40% load for Chrome).
Sometimes I have to restart Chrome since it becomes too slow.
When I do not use Inspector - it works quite fine.
And I usually use Inspector only for testing card-mod.
Q1: Is it normal for Chrome to become so slow when using an Inspector?
If not - should I change something in Chrome’s settings?

Also, as I understand, a code for some particular view works only when I open this view in my browser.
And some part of this code works on RPi, some part - on my PC.
That means that I can have lots of views in my HA setup, and it will not make my HA slower - unless I open some very complex view. But - this is just my opinion, my knowledge about HA internal structure is very poor.
Q2: Since I have a separate dashboard with ~20 views for testing card-mod - may it slow down my HA when I do not open this dashboard?