X has made another important change for "X Numbers". Now you have the option of showing/hiding your "X Number" from mutuals. When you have it set to off , anyone you follow, as well as anyone you have responded to in XChat can see your X Number ( even if they didnt use it to first talk to you). This means your mutuals can also give your X Number to others to allow people to chat or call you directly via XChat, bypassing the "message requests" box. When set to hidden it is not shared with anyone except those you specifically give it to. You can always refresh your X number as often as you want , which disables any previous X Number that was previously exposed and essentially locks your inbox down again. Thanks to @aditya_A17 for spotting this change.