[IMP] Core/Memory: remove one indentation in tests

doc/technical_choices.md

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+
+# The diff strategy
+
+## The simple strategy vs diff strategy
+It would be simple to make the change in our API, then change the related nodes
+in the DOM. But there is some problems that we need to address.
+
+So rather than 2 steps (direct strategy):
+1) apply in VDOC
+2) apply in DOM
+
+We do 4 steps (diff strategy):
+1) apply in DOM
+2) apply in VDOC
+3) diff DOM-VDOC
+4) apply in DOM
+
+### Problem 1: Dictionnary and spell checkers
+When preventing an event, if the dictionnary was saving data, it does not clear
+it's internal memory. So when another event happen, the dictionnary has wrong
+data and might create strange correction.
+
+[provide examples]
+
+### Problem 2: Mouvement between words
+When you have a word and you hit `ctrl + arrow`, you want to move from one word
+to the other. In some language like Lao, the words might not be separated by
+spaces. In order to know where is the delimitation of the word, we allow the
+browser to move the cursor and we reflect that navigation change in our VDOC.
+
+### Problem of the diff strategy
+Because we need the event to happen in the DOM it is possible that our VDOC will
+have a different rendering then what the browser registred. In such case, glitch
+can occurs.
+
+[Provide gif images to show a glitch]
+
+### Exceptions
+It is possible in some case to be sure that there is no dictionnary/spell cheker
+running or that we can predict the movement of the words. In such case, we
+can use the browser `event.preventDefault()` and therfore avoid any possible
+glitch.
+
+### Alternatives
+Ckeditor: deactivate the spellcheck alltogether and use third party plugins.
+
+Quilljs: ?
+
+