Windows 95/NT4 compatible plug-ins?
Is somewhere exist list of all NSIS plug-ins, which are compatible with old Windows systems, starting from 95/NT4? Checked wiki, but not all pages contain info about supported OS versions.
There is no list. There is also a big difference between a clean Windows installation and one with the shell update and IE5, those would be closer to Win98/2000 in some cases.
It makes little sense to write new installers for these old systems today. Anything older than XP is simply not worth dealing with.
Is there a specific plug-in you are interested in?
Well, the main thing that it should work at W95/NT4 (since i'm planning to make some software to Win9x and maybe old Win NT), so if it's important to install some updates for plugin support - that's not a problem.
About specific plugins:
1) Plug-ins for checksums calculation (if NSIS hasn't such function by default), or plug-ins with faster checksum even on old hardware (if NSIS 3.x hasn't the fastest way to calculate it).
2) Plug-ins for proper CPU architecture detection (especially for old hardware) of instruction sets like SSE and etc (if NSIS 3.x hasn't such function by default).
3) Plug-ins for advanced graphical or/and sound customisation of installer (just interesting if such stuff even existed for usage on old Windows, not so important for me).
Also, it would be great, if these plug-ins won't break installer compatibality even on latest windows 10/11 ( if NSIS 3.x installer in ANSI mode could itself proper works in all windows, from 95 to 11).
1) The Crypto API does not exist on 95 RTM. If you can require OSR2 or IE3 then
https://nsis.sourceforge.io/Crypto_plug-in would work. If not, you must check the other plug-ins, some might include the hash calculation code internally.
https://nsis.sourceforge.io/CRCCheck_plug-in perhaps.
2) IsProcessorFeaturePresent does not exist on 95, try
https://nsis.sourceforge.io/CPUFeatures_plug-in or
https://nsis.sourceforge.io/CPUDesc_plug-in
3) MUI2 should work.