The Sony Xperia 10 II (pronounced as Xperia 10 “Mark 2”) is the latest mid-range smartphone from the Japanese OEM. The smartphone offers Sony's signature 21:9 aspect ratio and a triple rear camera setup with dedicated ultra-wide angle as well as telephoto sensor, but a somewhat dated Qualcomm Snapdragon 665 SoC might be a disappointing factor for potential buyers. Sony has already published the kernel source code corresponding to this phone and added it to their Open Devices Program in a bid to promote third-party development. And now, the OEM is adding official support for unlocking the bootloader of the Sony Xperia 10 II.
Sony provides AOSP build guides through the Open Devices program wherein experienced developers can utilize the device tree as a base to port popular custom ROMs like LineageOS to the Xperia 10 II. You can't boot a custom ROM or even a GSI without having an unlocked bootloader, which means the arrival of official bootloader unlocking support should help kickstart true aftermarket development on the device.
As usual, you can head over to Sony’s online bootloader unlocking portal and follow the required steps to get the bootloader unlocked. In case you can't locate the exact model, no need to worry—Sony mistakenly lists it as the "Xperia X10 II".
It is worth mentioning that unlocking the bootloader of Sony Xperia devices wipes out the trim area (TA) partition that contains the DRM keys. You can't access Sony’s proprietary audio and video features without those unique keys, but at least Sony doesn't break the camera functionality anymore. On the other hand, some carrier variants of the Xperia 10 II may not be qualified for bootloader unlocking. You can verify that from the service menu by dialing *#*#7378423#*#* in the default dialer app and checking the eligibility under Service info > Configuration > Rooting Status.