Tumblr

The Tumblr account of Pangent Technologies, believed to be run by Charlotte (C/Lottie). The Tumblr is set in the exact same time period of the Pangent Twitter account, which appears to be long before the Youtube account etc. A large portion of the story takes place on the Tumblr. While there are no obvious puzzles or ciphers at this point, there are often posts at the Twitter which line up with those at the Tumblr in real time.

All posts on the PT Tumblr are tagged "PT" so they can also be read in chronological order. If a post is untagged, players should probably notify the Twitter.

"100% of my job is writing the same thing twenty times until someone gets it or it doesn’t matter anymore." - Argentina, Tumblr

"My life has the deepest lore. You don’t even know." - Argentina, Tumblr

The Birth of Tumblr
On 16 February 2016, User Reno found a link to http://pangenttechnologies.tumblr.com. (I believe the Tumblr was first linked by /four in the Chatzy, though my memory on this is not clear.)  When the Tumblr was first created, it was thought of as a joke due to the reposts of Sergio Agüero and Jeff Goldblum. Shortly after, it posted a GIF set of a scene from iRobot, a movie starring Will Smith, talking about whether robots can create art. Subsequently, it reblogged about the recent merging of two black holes and about cardioids.

(As the Tumblr became more and more important later, it became a sticking point that the chat had considered it a joke for days and missed hundreds of clues in the process.)

The First Images
On the same day the Tumblr was created, an image was uploaded to it. The woman in the image was not seen in this position before, and was also wearing clothes different from any other video the community has seen so far. There were two more posts, one talking about missing London and the other an image of the woman.

Making X Cry
As the Twitter account user (which was at that time X) started crying, the Tumblr account started posting about "deleting ten thousand Twitter posts" and "deleting anything personal". The Tumblr also posted about how the person crying has just become her boss. A few moments after, there was a generic post on both the Twitter and Tumblr saying "Any information and views I may have shared since May 2010 are my own views and do not represent those of my employer, Pangent Technologies."

Leslie's Turn at Twitter
After a few personal posts, Charlotte mentions that Leslie has "hit her head, she’s unconscious" after "trying to physically strangle Twitter".

PT
The Tumblr account seemed (and is) much more light-hearted and comedic than the Youtube channel, though it later had moments of very grave seriousness. We find out quite a bit about the day to day frustrations of working at Pangent, through the account's sense of humor. We meet "The dreaded X," her assistant who becomes her boss and rival. There is also Sharon, her assistant, and Leslie, X's assistant. She talks about her traumatic accident and E, a "weird" male friend (presumably Eric).

After X makes the company look bad on Twitter, the company's entire social media strategy comes under scrutiny. X is promoted while she is demoted. She was previously a top scientist at their London and Buenos Aires offices, but now ends up writing code and running damage control. She deletes most of the archives of both the Tumblr and Twitter accounts. Then management asks for this data back. Desperate and sleepless, she uses Twitter itself to try to recreate the data. (This played out in real life with about a dozen actual live users from the Chatzy, who she believed were just bots.) This is actually data from the Youtube Channel, marked as coming from the year 2020. She is in December 2016 and cannot see the videos.

Some of the data is recreated thanks to those users, but when attempting to recreate the entire account, she crashes the Twitter account and Pangent's server. Pangent's Twitter becomes an egg account and the Pangent website vanishes (this was always true in real life, but not from her point of view in the story). She panics, having a nervous breakdown, and is unable to recreate the website.

She is fired - temporarily? - by X and leaves with E for a Christmas vacation.

Christmas Break / Leslie Takes Over
http://pangenttechnologies.tumblr.com/tagged/PT/chrono/page/15

On page 15 of the blog, X's assistant Leslie takes over, replacing The Woman/Argentina. Her messages are coded with the key mayorsassenheim, named for her cat.

X also writes several posts in code.