Assembly-CSharp.dll size changes with code stripping

1. What happened
Assembly-CSharp.dll after code stripping became larger by 512 bytes.

2. How we can reproduce it using the example you attached
In the attached project see webgl1_1/Managed folder (copied from my project Temp). Compare sizes for Assembly-CSharp.dll here and in tempUnstripped.
Project was built for WebGL release configuraiton.
Project content is 'Tanks Tutorial' package from Assets Store.

For the same project in 5.4.1p3 stripped Assembly-CSharp.dll is by 512 smaller.