Do* people know what mc, fl and ml mean

Thses are abbreviation for main character, female lead and male lead

I keep writing the full words like main character instead of mc because I'm afraid that people won't know what this means and won't give me some suggestions as I've seen ot before

But I would really like to get things done quicker and save some time so I was just wondering if at least 90% of people know what i mean if i said fl because i don't useally get many replies in my topics and don't want to lose any potential answers that i get

I would guess a lot of people would know. Several forums and even comment sections I visit use them all the time and rarely ever use the full terms unless explaining what the abbreviations mean. Even someone who doesn't know would get it just by context of how people use them in their sentences.

Okay thank you

I think you only lose answers by being too specific/not specific enough.

Mc is commonly understood by pretty much anyone doing any kind of reading, manga or not. Ml and fl are less commonly used and people tend to go halfway there with male/female mc.
That being said, unless you severely misconstructed your sentence people would probably still understand from context. Especially on a manga forum.

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Just my personal experience, I can understand ML and FL easily in the context, but many time people use MC to refer to one character so it's a bit confusing to me to guess which character they're mentioning.

My approach is to spell out the meaning in parentheses after the first use.

Ex. So, the MC (main character) just insulted the other MC, and now the two hate each other.

I'm a jack of all trades but master of none. Too many jars and not enough hands.