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[ ] support request => check the FAQ and search github for a similar issue before submitting
[ ] feature request

Current behavior

When i'm using translate directive, text don't translate, key still here

// en.json
{
  "key": "en-value"
}

// fr.json
{
  "key": "fr-value"
}

// page.html
<p translate>key</p>

// result 
key

// use translate.use('fr') in ts file
// result
key

Expected/desired behavior

// en.json
{
  "key": "en-value"
}

// fr.json
{
  "key": "fr-value"
}

// page.html
<p translate>key</p>

// result 
en-value

// use translate.use('fr') in ts file
// resultf
fr-value

Reproduction of the problem

I don't really know how to reproduce this problem, I just installed ngx-translate on my Angular project like it's say on the Getting Started

What is the motivation / use case for changing the behavior?
Just want to translate using directive, and string between tag as key (like described on the readme)

Please tell us about your environment:

• ngx-translate version: 9.1.1

• Angular version: 5.0.3

• Browser: [all]