Some user using IPA symbols asked me about the following:
the need is to type
t U035C s
where U02A6 is the ts ligature.
Of course if one types t s U035C then the solution is trivial. But the need is to type with this order: t U035C s
since there is a lot of linguistic material already typed in this order. They were "trained" to type in this order since older fonts were placing U035C under t in such a way that was extending to the right, and s was falling at the right place. But those older fonts did not have or provide a ts ligature (U02A6).