How to prevent bcftools to modify homopolymer representations ?

[yvanw]

Hi,
Is there a way to prevent the alteration of variant representations when merging files ?
As an example, I am using these variant representations, that keeps the length of hompolymers visible
REF: TAAAAAAAAAAAAAAAA --> ALT: TAAAAAAAAAAAAAAA

After runing bcftools merge, I obtain REF: TA --> ALT: A (which is also correct, but the information about the homopolymer size is lost)
Thanks for your inputs !
Yvan

Ps. I am using bcftools version 1.9