diff --git a/Firefox-webext.md b/Firefox-webext.md
new file mode 100644
index 0000000..b28d2a2
--- /dev/null
+++ b/Firefox-webext.md
@@ -0,0 +1,34 @@
+The webext (-hybrid) version of uBO ("uBO/webext") has been released to the [dev channel on AMO](https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/versions/beta) starting with 1.13.9b0.
+
+### First install
+
+The first time uBO/webext executes, there might be a noticeable delay (a few seconds): this is caused by the fact that uBO/webext will import all the data from legacy storage, into webext storage. This is done only the first time the uBO/webext is executed, after this the import step will be skipped.
+
+If you subsequently remove uBO/webext, this will cause the webext storage to be removed by Firefox, and upon re-installing uBO/webext version, the import code will again kick in.
+
+Note that uBO/webext will still be labelled as "Legacy" in `about:addons`, because uBO/webext is really a [webext-hybrid extension](https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Embedded_WebExtensions). Once the legacy storage has been imported at first install by the thin legacy wrapper, uBO/webext will fully function as a pure webext extension despite the "Legacy" label.
+
+The legacy storage is left untouched by uBO/webext, so you can always go back to uBO/legacy (stable release) if you do not want to use the webext version in the short term.
+
+### Firefox for Android
+
+As per [documentation](https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Differences_between_desktop_and_Android), only with Firefox Mobile 55 (beta) you can access uBO's popup panel.
+
+However it appears there is an issue with installing webext extensions on Firefox for Android 55, the browser thinks the extensions are corrupted -- this does not appear specific to uBO/webext. Consequently, for now it seems it's best to stick to uBO/legacy on Firefox for Android.
+
+### Differences with uBO/legacy
+
+- `script:contains` filters will stop working
+    - uBO's own filter lists have long ceased to rely on this filter syntax to solve reported filtering issues.
+- ~~cosmetic filters will no longer use the browser's user styles~~ [Fixed with f32868766340e2fb8ec689f4b5683a413de847b6](https://github.com/gorhill/uBlock/commit/f32868766340e2fb8ec689f4b5683a413de847b6)
+- uBO/webext has limited access to behind-the-scene network requests, unlike uBO/legacy which had full access to all behind-the-scene network requests. For example, you won't be able to see (and block) network requests made by other extensions.
+
+### Future of uBO/legacy
+
+For all those Firefox and Firefox-based browsers based on Firefox v53 and less, the dev channel of uBO will cease to work, and they will have to install manually the `xpi` version from the repo here if you want to keep using the dev version of uBO, or install the [stable version of uBO on AMO](https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/).
+
+As of writing, there is no plan to cease development of uBO/legacy. Hypothetically, this may change in some future if ever it becomes really non-trivial to keep a working the legacy version.
+
+### Miscellaneous
+
+[Issue #2795](https://github.com/gorhill/uBlock/issues/2795) will be a collection of [bugzilla.mozilla.org](https://bugzilla.mozilla.org/) issues which currently affect the uBO/webext specifically.
\ No newline at end of file