Any way to build for stable channel?

[AlexKovalevych]

Getting compile errors on stable channel:

error[E0554]: `#![feature]` may not be used on the stable release channel
 --> ~/.cargo/registry/src/github.com-1ecc6299db9ec823/plex-0.2.5/src/lib.rs:2:12
  |
2 | #![feature(proc_macro_diagnostic)]
  |            ^^^^^^^^^^^^^^^^^^^^^

error[E0554]: `#![feature]` may not be used on the stable release channel
 --> ~/.cargo/registry/src/github.com-1ecc6299db9ec823/plex-0.2.5/src/lib.rs:3:12
  |
3 | #![feature(proc_macro_span)]
  |            ^^^^^^^^^^^^^^^

I'm able to manually just remove those features and unstable functions for personal usage (in fork for example), but in general, any plans or ideas how to correctly get rid of them?