Many of the commands and functionalities for editing the content of the RadEditor control depend on the browser commands.
Functionalities like bold, italic, indent, outdent, font sizing etc. are actually implemented in the browser's logic. Due to historical reasons and the complexity of implementing custom functions for these features the editor from RadControls v2009.1.402.20 is using the available browser commands.
For the time being, along with browser upgrading, these commands have been changed in order to stabilize the RadEditor's and make it work as expected.
I could only make assumptions on what modifications have been made to the browser commands in Chrome and I cannot suggest you a proper solution for the described issue.
I would recommend you to upgrade RadControls to version, which corresponds to the Chrome version you are using, so that any bugs or issues that occurs in older versions would be fixed.
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