I sent a ticket to HTC with detailled information and got a copy/pasted response from support asking lot's of question that were already provided. I decided to not waste more time and I'm returning it to B&H where I purshased it.
I don't trust my device anymore, this is a high-end and expensive device and it should works normally under normal usage. 4 days and a broken display and the fact I counted so far at least 10 people with the same issue on reddit make me think that the headset is not ready and the quality control was rushed.
After the firmware update and after leaving the box unplug for 48 hours, the line seem to have fade away but at 50%, now I'm seeing mostly some grayed line at the same place, harded to see but still there but what important, this is a defect, what else will happen ? why this happen? overheat? so anyway, my defective device will be returned as soon as I get my shipping label.
I'm lucky to have purshaced it at B&H instead of HTC since I would have been stuck to a massive Quality Control report for them, I lost enought time already, they need to do their own quality control and debugging and not ask the customer to do it for a device of this price.
This is exactly my issue, found it on reddit from another user.
This youtube got the problem 2 weeks ago: