I have been a huge fan of Firefox since, like, ever.
Do you remember Moox? Nope? Well, I do.
It has its ups and downs but it is a Good Browser in general; it offers a proper balance between usability and respecting users' privacy.
Since around version 37 Firefox brings a new feature called "Reader View". It is quite simple but powerful: it can display the current web page in a "reading mode" which is simply stripping-off any non-textual data and also presenting whatever is left in a nice, single-column view, perfect for reading.
I find this feature very useful, especially on websites with poorly configured font sizes and / or typefaces.
I write a lot. Mostly in Polish.
There are nine diacritics in the Polish alphabet: ż, ź, ć, ń, ą, ś, ł, ę, ó (this is the order they appear on the keyboard, left-to-right, bottom-up).
Except for some exotic, one-in-a-milion scenarios, all Polish keyboards use the standard "polish-programmer" layout which allows for entering the nine diacritics simply by pressing RAlt key and then the actual letter.
So: RAlt-o for ó, RAlt-n for ń and so on. The only exception is ź (RAlt-x) as RAlt-z is already taken for ż.
Now, if you take a peek at your keyboard, you will see that E and R keys are close to each other. So when you try to type "ę" (RAlt-e) it is easy to hit RAlt-R instead.
Guess what combination activates the famous Reader View in Firefox.
Imagine typing a loooong, long comment or a blog piece or anything else, in your favourite web browser, and instead of hitting RAlt-e (for "ę") you hit RAlt-r (because your index finger just slipped a little bit to the right).
Your momentarily not-so-favourite, stupid, ridiculous, insane web browser switches to Reading View, effectively destroying everything you just typed.
I cannot count the number of times I got frustrated (and so did the entire Internet by not being able to present my priceless thoughts to the humanity) because my left index finger slipped a little bit to the right.
So recently I finally decided to chop off this stupid thing in order to preserve the tiny amount of sanity still remaining somewhere inside my skull.
I disabled the Reader View.
Thankfully, as with most other things in Firefox, there is a hidden option for it. Just browse to about:config, find the following setting:
...and set its value to false, then restart Firefox and Bob's your uncle.
You're very welcome!