TWRP is the most popular custom recovery thanks to the huge number of devices it supports and the features it offers like full backups and restores, touch support, slot selection, and more. TWRP has been the go-to recovery for those interested in modding their smartphones. Whether you qualify as a newbie in the flashing scene or as an experienced flashaholic, you’ve almost certainly used TWRP at some point. The custom recovery isn’t perfect on every device, however, as Android updates may bring changes to the kernel, ramdisk, encryption algorithms, etc. that require TWRP to adapt. For instance, data decryption wasn’t working on the Google Pixel or Google Pixel 2 running on Android Pie.
If you have a Google Pixel device, you likely have a PIN or password on your device to secure your phone. If you wanted to make a backup or flash a file stored on your internal storage, you would have to remove the PIN or password before booting into the recovery so encryption would be disabled. Fortunately, Dees_Troy, the lead maintainer of the custom recovery, has announced that the issue has been fixed. Version 3.2.3-1 of the custom recovery is now able to decrypt the data partition after entering the PIN or the password set on the device. The new version is available for Google Pixel, Pixel XL, Pixel 2 and Pixel 2 XL.
You can download and install the newest version of TWRP from their official website, linked below, or by using the official app.
Source: Dees_Troy (Google+)