<li>rEFInd attempts to guess the Linux distribution based on data in the <tt>/etc/os-release</tt> file. This file will only be accessible if a separate <tt>/boot</tt> partition is <i>not</i> used, though. Manually adjusting the <tt>os-release</tt> file to change an OS icon in rEFInd is <i>not</i> recommended.</li>
<li>Certain boot loaders have hard-coded icons associated with them. For instance, filenames beginning with <tt>vmlinuz</tt> or <tt>bzImage</tt> acquire Linux "Tux" icon and the <tt>bootmgfw.efi</tt> loader acquires a Windows icon. Fedora and Red Hat kernels can be identified by the presence of <tt>.fc</tt> or <tt>.el</tt> strings in their filenames, and so acquire suitable icons automatically. For the most part, these are the associations you want to overcome with the preceding rules, but sometimes renaming a boot loader to a more conventional name is the better approach. Renaming a locally-compiled kernel so that it acquires a Fedora or Red Hat icon is reasonable, but I don't recommend renaming precompiled kernels unless you also manually copy them to the ESP.</li>
<li>rEFInd attempts to guess the Linux distribution based on data in the <tt>/etc/os-release</tt> file. This file will only be accessible if a separate <tt>/boot</tt> partition is <i>not</i> used, though. Manually adjusting the <tt>os-release</tt> file to change an OS icon in rEFInd is <i>not</i> recommended.</li>
<li>Certain boot loaders have hard-coded icons associated with them. For instance, filenames beginning with <tt>vmlinuz</tt> or <tt>bzImage</tt> acquire Linux "Tux" icon and the <tt>bootmgfw.efi</tt> loader acquires a Windows icon. Fedora and Red Hat kernels can be identified by the presence of <tt>.fc</tt> or <tt>.el</tt> strings in their filenames, and so acquire suitable icons automatically. For the most part, these are the associations you want to overcome with the preceding rules, but sometimes renaming a boot loader to a more conventional name is the better approach. Renaming a locally-compiled kernel so that it acquires a Fedora or Red Hat icon is reasonable, but I don't recommend renaming precompiled kernels unless you also manually copy them to the ESP.</li>