Timeline, a feature introduced to the general public with version 1803 (the April 2018 Update of Windows 10), hasn't taken off with the developer community perhaps quite as quickly as it should. However, three months after its debut, while still being reasonablyMicrosoft centric with apps like the Office suite or Edge, third-party offerings such as VLC have also mad use of Timeline to sync app activity across devices.
To enhance the current capabilities for the subset of Windows users that prefer Google Chrome, Firefox or Vivaldi, and would like to utilize Timeline as a quick way to reopen recently closed browsing sessions, there's good news. This comes courtesy of Dominic Maas, developer of SoundByte, a slick third-party UWP app for SoundCloud.
Maas has created an add-on, self-explanatorily called "Windows Timeline Support", for these browsers. It allows them to tap into Timeline by hooking them up to your Microsoft activity history, effectively making prior browsing sessions visible to you with a simple Win+Tab shortcut. A sign-in to your Microsoft account is necessary through the plug-in, though it's only a one-time affair.
An additional Timeline-based feature this add-on gives users is the ability to push open tabs on your browser of choice from one Windows device to another, previously possible only on tabs open in the iOS or Android version of Edge.
Source: Dominic Mass (Twitter)