(Summary) 
I made a account a while ago.
Installed addons, skin packs, worlds from marketplace.
Caused issues.
Examples are below.
Not connecting to world, realms, or servers as intended.
Game Freezes because of marketplace content.
Tested without marketplace content and issues didn't happen again.

(Long Explanation)
So to summarize the issue here is the problems. In this report i made it has 2 issues that are being cause by the same thing. The problem is when you have a group of addons added to your Minecraft account the game will freeze up around every 20 seconds and it will stay froze for around 5-3 seconds. My other issue is connection issues being caused by addons/marketplace content. I ran a bunch of test and i wrote about them in the big text below. To summarize my test i had 3 accounts 1 being my main. I found this was being caused by addons by accident, I made a new account because i wanted to get rid of the issues i was having which are the Micro Lag and the Connection Issues. I will show examples of both below.  On my alt account i didn't install any marketplace content and played with it for around a week and a half. i noticed that i was able to join all games, realms, and servers almost 100% of the time. But the game was telling me that it was a "connection issue" so that's what i thought it was, but i found out it wasn't my connection at all. So i ran a few test, long story short once i installed some skin packs, global resource packs, and addons my alt accounts game began to do the same thing as my main. Both of the issues got worse with the more connect installed. I will now post the pictures and videos of the issues below. I have ran a bunch of test by making a bunch of fresh accounts and testing it. if you have no addons or nothing bought from the marketplace it runs amazing. But when i installed addons on another account i started to get to lag again. And ALSO this effects connected to realms, servers, and your friends worlds as well, so i tested connected to realms, servers, and my friends world 100 times without addons and 100 with addons. in the test where i did it WITHOUT addons it joined perfect besides one time with my friend out of 100 but i think i was cause of his wifi, anyways. When i did it with the addons i had a lot of problems this happened with servers, realms, and friends worlds, when ran Minecraft on the account with addons i wouldn't let me join ANYTHING i kept trying to join servers for about 60 try's and couldn't get in a single time so i decided to try realms, so i tried for about 30 try's and i couldn't get in so i tried doing a trick to get in, so what i did is i click the realm and as soon as the "cancel" option showed up i closed it and tried to rejoin the realm as fast as i could and it worked, but i would always say "oops ! Your Microsoft account was disconnected to invite more players, sign in on the main menu and restart your world" and it would kick me out after 30 seconds of playing and this would help me get into realms 100% of the time. so i decided to try my friends world and after around 30 try's i gave up, i reset my game and kept joining and it didn't work, i also logged out and logged back in and it still didn't work. i went offline and online and still nothing. so i just went back to trying to joining and leaving and after around 50 try's and a lot of time i finally got in. now im guessing that the more addons you have the harder the micro lag is and the connection issues are. i don't know if its the size of the addons or just the number of addons but this is a huge bug and i have a lot of friends who just shrug it off as there internet but on a alt account it works fine. thanks for reading this and please don't just say its a copy. i have spent hours looking on here and nothing matches this. thank you <3