Use mega.nz
I switched from Dropbox to MEGA as my default cloud file host a year ago, can confirm that there are no issues, ads or other bullstuff.
As for the ads on Mediafire, I have AdBlock on Google Chrome and I still see them too directly after pressing the download button: most of the time it's a Roblox registration ad (no kidding), but occassionally there'll be something malicious i.e. "your PC is infected" or similar.
We have Pecon's justfilehosting.space, Hostr, Dropbox and MEGA.
please stop using Mediafire.