I can't find any dot files as .vimrc, .bashrc. Is it supported?

The default commands fzf uses do not include hidden files. If you want hidden files in the list, you have to define your own $FZF_DEFAULT_COMMAND or $FZF_CTRL_T_COMMAND depending on the context.
For example:
export FZF_DEFAULT_COMMAND='ag --hidden --ignore .git -g ""'
When I try export FZF_DEFAULT_COMMAND='ag --hidden --ignore .git -g ""' fzf stops working in bash shell and lists no files at all (not only dot files, but nothing at all) but it works as expected in vim. I modified the default command and tried export FZF_DEFAULT_COMMAND="find . -path '*/\.*' -type d -prune -o -type f -print -o -type l -print 2> /dev/null | sed s/^..//" and fzf worked as expected both in bash and in vim. I guess this is related to how ag generates its output?
@nimamo Have you checked the command itself (ag --hidden --ignore .git -g "") works in bash?
@junegunn Yes and it works as expected.
@nimamo How about ag --hidden --ignore .git -g "" | cat? If it fails, upgrade ag.
@junegunn This command works. I tried the same procedure ( export FZF_DEFAULT_COMMAND='ag --hidden --ignore .git -g ""' ) on a different Linux installation and it just worked fine. This doesn't seem to be a bug in fzf, yet seeing different results from fzf in bash and :FZF in Vim is worth noticing.
@nimamo Please make sure you have the latest version of ag installed. Probably related: #573
The command to use rg (ripgrep) instead of ag (the_silver_searcher):
export FZF_DEFAULT_COMMAND='rg --hidden --no-ignore -l ""'
I get the following [Command failed: ag --hidden --ignore .git -g ""] even though I do have ag installed
See if $SHELL -c 'ag --hidden --ignore .git -g ""' works on you shell because that's what fzf does.
A faster command for ripgrep is
export FZF_DEFAULT_COMMAND='rg --hidden --no-ignore --files'
which does not search the content of files.
Most helpful comment
The default commands fzf uses do not include hidden files. If you want hidden files in the list, you have to define your own
$FZF_DEFAULT_COMMANDor$FZF_CTRL_T_COMMANDdepending on the context.For example: