The script will actually read from the comment feed of your blog, just like the post feed we usually subscribe to. The script below can be customized to the number of comments and the length of comments to be shown.
It will just take you a few steps to do in Blogger so here are the steps.
1) At your Blogger dashboard, select Layout.
2) Click the Add a Gadget link from the section you want the recent comments to appear.
4) From the title, add your desired title, for me Recent Comments is just right.
5) Paste this code on the content
6) Make sure to change the BLOGGERNAME from the script.
7) The script is set to display the 5 recent comments and show the first 100 characters of the comments. Replace the value of a_rc=5, 5 being the number of recent comments to be displayed. Replace the value of o_rc=100, 100 being the number of characters of comments to be displayed.
8) Click the Save button to reflect the changes in your template.
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