when starting Arduino IDE new install:
no premature abort possible shortly after starting, either mistakenly clicking download or zip for an easily overlooked portable option.
OTOH, "download" is ambiguous because actually also the portable version is a "download".
So instead there must be 2 differently termed install button links:
[X] install to the Windows Programs(0x86) folder
[X] download the portable version (zip file) to your harddisk

Additionally, there is a deficiency in the installation program:
I actually wanted to install a portable option, but after mistakenly clicking the link "download", the installation to the Windows Programs(0x86) folder is started immediately, and after having recognized that it cannot be stopped anymore - just the extra features can be skipped.

So there must be confirmation buttons before executing the installation:
[X] start installation to the Windows Programs folder
[X] Abort