Font rendering in firefox, problems with the letter "I"

Question

Design

Faced with the problem of rendering fonts in the Firefox browser. If you write the letter "I" as taught at school, you get 2 vertical sticks, between them there is a rounded connecting line. If you write the way children first learn, i.e. “with sticks, then you get 2 vertical sticks, between them is a straight line, located from the bottom up. I was faced with a task where it is necessary to draw the letter "I" exactly the way they teach at school. Fonts from the standard set that support such spelling are displayed normally in other browsers. But “gnelis” stubbornly refuses to make the letter round. How can I overcome the problem without using images and third-party fonts?

Answer 1

2ragimovich: absolutely true
2All: I'm sorry, maybe I asked a bit chaotically. By nightfall, my head was already in a bad state of mind.
Here is the text code:

<div style="font-family: Arial">и И</div>

For those to whom my stream of consciousness seemed incomprehensible, here is how firefox depicts the letter “I”:
And here is how the letter “I” of some fonts is displayed by all other browsers:
I selected different fonts from the “safe and recommended for the web” set. In some - the style is the same as in the first picture, in others - as in the second. I tried chrome, explorer, opera, safari everywhere it was fine and only in firefox all fonts render the letter as in the first picture.