Instructional Text button does not work as expected

Issue Summary

This is reproducible on the Data Center: yes

Steps to Reproduce

Scenario 1:

1. Go to the space and select Space tools > Content Tools from the bottom of the sidebar
2. Choose Templates > Create new template.
3. Add a name to the Template
4. Now click on the "Instructional Text button"

Expected Results

The cursor should become italic and the text written afterwards should be light gray with a light gray shadow

Actual Results

Nothing happens

Scenario 2

1. Go to the space and select Space tools > Content Tools from the bottom of the sidebar
2. Choose Templates > Create new template.
3. Add a name to the Template
4. Now add a new Line
5. Now click on the "Instructional Text button"

Expected Results

The cursor should become italic and the text written afterward should be light gray with a light gray shadow

Actual Results

The instructional text box appears after the text and typing pushes the box forward. Cannot move the typing icon to type in the box.

Scenario 3

1. Go to the space and select Space tools > Content Tools from the bottom of the sidebar
2. Choose Templates > Create new template.
3. Add a name to the Template
4. Now add a new Line
5. Now click on the "Instructional Text button"
6. Press Enter , this will give "Instructional Text box" on the new line
7. Now add some text to the box
8. Add a new line after this box
9. Save the template
10. Now try to create a new Page using the above created template
11. Once the page is created , start tying in the instructional text box

Expected Results

The cursor should become italic and the text written afterward should be light gray with a light gray shadow

Actual Results

When writing in the instructional text box, the line gets deleted completely and the written text is at the beginning of the next line

Workaround

1. Install "Confluence Source Editor" add-on
2. Go to Space Tools > Content Tools > Templates or go to     > General Configuration > Global Templates and Blueprints
3. Locate/Create the template to which you would like to add the instructional text
4. Click on "Edit"
5. Click on "<>"
6. Add instructional text between <ac:placeholder> tags. i.e:

   <ac:placeholder>Some Instructional Text</ac:placeholder>  

1. Save the template