Constantly asking to change permissions on Android. It became so annoying I had to remove it altogether.

It is a cool idea and helps a lot with my dyslexia. But it works properly less than half of the time.
1. Detecting the text correctly, especially on websites where text is separated by other content or when there are multiple columns.
2. Often the reading out does not stop when click pause or stop, I have to close all Firefox windows to make the reading out stop.

Piper's voices are really good. I really appreciate the automatic language selection.

The voice is good, but the controls don't do jack. The pause button does absolutely nothing ever, and the second time I tried the add on the highlighted text didn't match what was being read (no idea where in the document it was reading from) and this time I had to close the browser entirely to make it stop reading.

Solid add-on, but the fact that you need to have an entire tab open in order to use the new piper.ttstool voices makes the add-on much less convenient

Adding the piper voices is a game changer!! Thank you Dev.
Initially, I was pretty unhappy with the robotic voices and decided to read the reviews and found the same complaints. Then I saw that there was an update a week ago and, lo and behold, you can now add custom voices from piper that sound so much more human. It's a night and day difference. Makes this so much more worth it now. Even though it's still in the experimental phase, it works just fine for me.
I urge everyone to try it out in settings.

نسخ الكلي

Great

The default voice is unintelligible and the other voices are not much better. This is a joke of an app.

Used this for like years to make my novels audiobooks and the desktop browser version of it works pretty well. IMO, the only good TTS voice is the microsoft zira one lol. Works very well for what it is, but the in-built firefox reader also has a TTS function, which is essentially the same thing. I don't discourage people from using this extension though, since it comes in handy when you just need one specific section TTS'd and it's quicker to activate than the in-built one.

An issue I found only on the desktop browser is that the highlighted text would jump ahead of the actual text the extension is reading and it would continue reading the text even if you press 'stop' (only in the case of the jumping highlighted text). Found that if this happens, press 'test' in the settings and the 'stop' after and it'll stop. Kind of annoying though since it happens every so often.

On the other hand, the mobile version of the extension is kinda meh. The issue I mentioned before doesn't seem to exist on mobile but a different one cropped up. On certain sites, or pages within the sites, the TTS randomly decides to change their voice to another. Again, only microsoft zira is listenable so it forces me to just stop the TTS and read manually.

Also, the 'sign in to use premium voices' have never acutally worked for me on mobile. Every time I click 'sign in', nothing appears T_T, lowkey frustrating. And apart from the offline voices, all of the voices don't work when I'm running on data. They do work when I'm using someone elses hotspot tho :(. Frustrating since I usually want to use mobile TTS when I'm out and about.