-preview=safer for D

[Sergey]

On Friday, 3 January 2025 at 15:43:01 UTC, Richard (Rikki) Andrew 
Cattermole wrote:
> On 03/01/2025 11:19 PM, Andrej Mitrovic wrote:
> However, given that this isn't meant to remain a switch, I am 
> unconvinced that it requires this treatment. Perhaps it 
> warrants discussion though.

Does D has an instrument to check how many people were using this 
switch?
To be able to analyze how useful was this feature