Some fonts do not work in Kompozer?
Users report this problem.
Go to Tools, options, then click Fonts, add checkmark in Allow document to use other fonts.

If problem persists?
You can add a snippet of code and change the font.

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How to Write eBook using Kompozer

When a font is functional, you highlight text, and select font from dropdown menu located on toolbar:
Old English Text MT

And Kompozer changes the text.

Old English Text works, however, some fonts do not work.

Footnote: you can add new fonts to your computer, such as Questrial.
earch internet for Questrial font. There are sites that offer free fonts or fonts for a price.
Typical method for adding new fonts: download font file from internet, extract and save to font folder located in Control Panel. The new font will automatically appear among fonts next time Kompozer is opened.

After downloading four new fonts and extracting to Font folder, I discovered:
Questrial works fine in Kompozer, Firefox, Chrome, and Kindle Previewer.
Indie Flower works in Kompozer, firefox and chrome, Kindle Previewer, but not my other computer.

1942 Report and 28 Days Later do not work voluntarily in Kompozer, but work elsewhere.
The fonts also work fine in Notepad, and Wordpad, but do not successfully paste into Kompozer.
Even saving Notepad in .html, hoping to copy the code into Kompozer, the font goes back to default, and not to selected font.
To solve problem, we can add a bit of code.
Click on Source tab at bottom of Kompozer workspace.
Paste any of the following into Kompozer source code on an empty line.

Example codes...
Kompozer default extra large font:
<font size="+2">Kompozer default extra large font</font>

Old English Text MT in default extra large font
<font size="+2">Old English Text MT</font>

Hightlight and change text in Kompozer
Old English Text MT
<font style="font-family: Old English Text MT;" size="+2">Old English Text MT</font>

Let's try 1942 Report using same code as Old English Text MC
<font style="font-family: 1942 Report;" size="+2">1942 Report</font>
<font style="font-family: 1942 report;" size="+2">1942 report</font>

Result, it doesn't add the correct font !!
Let's try a different way.

1942 Report in Kompozer default extra large size:
<font size="+2">1942 report</font>

1942 report in extra large size
<font size="+2"><span style="font-family: &quot;1942 report&quot;;">1942 Report<o:p></o:p></span></font>
<font size="+2"><span style="font-family: &quot;1942 Report&quot;;">1942 Report<o:p></o:p></span></font>

Result: this code works !!
Yes there are two ;; in the code.

Another example:

28 Days Later in default extra large font
<font size="+2">28 days in default extra large font</font>

28 days later in extra large font
<font size="+2"><span style="font-family: &quot;28 days later&quot;;"> 28 Days Later<o:p></o:p></span></font>
<font size="+2"><span style="font-family: &quot;28 Days Later&quot;;"> 28 Days Later<o:p></o:p></span></font>

Note also that you can make extra large Fonts in Google Docs and paste them into Kompozer.
Not every Google Docs font works in Kompozer.
For example, Merriweather size 48 will paste in default font only.
You can continue typing with the font
Or change to agency FB or Brush Script MT

You can change font size

Note also that you can make very large Fonts in Word Docx and paste them into Kompozer.
Not every Word Docx font works in Kompozer.
For example, Magneto will work no matter if you paste from Googe or Word.
You can continue typing..
Or change to Ariel
You can change font size
Read my new book posted on Amazon
How to Write eBook using Kompozer