title: Ionic 5 build with --prod flag fails - Property 'translate' does not exist on type
body: <p>I am developing an Ionic 5 project and when I run the build with --prod flag I receive the following error:</p>
  <pre><code>Error: src/app/pages/edit-profile/edit-profile.page.html(8,142): Property 'translate' does not exist on type 'EditProfilePage'.
  </code></pre>
  <p>I have traced it back to the following line:</p>
  <pre><code>&lt;ion-input clearInput formControlName=&quot;userName&quot; (ionBlur)=&quot;checkUserName($event.target.value)&quot; (ionFocus)=&quot;userNameFocus()&quot; placeholder=&quot;{{'USERNAME' || translate}}&quot;&gt;&lt;/ion-input&gt;
  </code></pre>
  <p>When I delete this line the build with --prod flag is successfull. It also builds without the --prod flag.</p>
  <p>This is my tsconfig.ts file:</p>
  <pre><code> {
    &quot;compileOnSave&quot;: false,
    &quot;compilerOptions&quot;: {
      &quot;baseUrl&quot;: &quot;./&quot;,
      &quot;outDir&quot;: &quot;./dist/out-tsc&quot;,
      &quot;sourceMap&quot;: true,
      &quot;declaration&quot;: false,
      &quot;downlevelIteration&quot;: true,
      &quot;experimentalDecorators&quot;: true,
      &quot;module&quot;: &quot;es2020&quot;,
      &quot;moduleResolution&quot;: &quot;node&quot;,
      &quot;importHelpers&quot;: true,
      &quot;target&quot;: &quot;es2015&quot;,
      &quot;lib&quot;: [&quot;es2018&quot;, &quot;dom&quot;],
      &quot;resolveJsonModule&quot;: true
    },
    &quot;angularCompilerOptions&quot;: {
      &quot;fullTemplateTypeCheck&quot;: true,
      &quot;strictInjectionParameters&quot;: true
    },
    &quot;exclude&quot;: [&quot;.history/*&quot;]
  }
  </code></pre>
  <p>Any ideas whats wrong here?</p>