Miiverse Glitches are usually not very common, sometimes they randomly occur or can be repeated over and over again by users to cheat the system.
Yeah Button Glitches
Olv.portal.miitoo was a glitch on Miiverse. It changed the yeah button's text to olv.portal.miitoo.It is not certain as to who first had the glitch, but it first became famous from the user MortifiedPanda (now perma-banned). It was fixed.
People whose posts had the olv.portal.miitoo glitch
In the prototype of Miiverse (or Olive, which was Miiverse's codename), the Yeah button said "Mii too":
A lot of Miiverse's functions started with "olv.portal"(since Miiverse's codename is Olive, it starts with olv).
"No Posts Have Been Made Yet" Glitch
This glitch happens often on Miiverse, and many users are annoyed by it. On occasion, if you go to someone's posts, the post counter will give the number of posts, but the post section says "No Miiverse posts have been made yet."
This can also happen on communities, though this does not happen as much as on users' profiles. Whenever this happens, the post section of the community will either say "This community doesn't have any posts yet" or "There are no posts to display."
This glitch still has not been fixed and probably can't ever be fixed.
Minecraft: Story Mode Blank Screen GlitchThis glitch happens when you enter Miiverse with Minecraft: Story Mode suspended. When you try to attach a picture, it shows a black screen and nothing else. This has only accord on Episode 1, as that's the only one that is out. Soon enough, they disabled screenshots entirely.
Post Refilling Glitch
When Day-Light Savings Time accord, many users posts wouldn't refill the next day due to that time, even though they fixed their clock on Wii U or 3DS. Either that, or only a certain amount of posts would be refilled.