This plugin is adding a very noticeable amount of delay when opening a new shell session

Hi,

I started to use this plugin recently and I noticed my shell sessions are taking quite a bit longer to open up. I've profiled a few things and here's the numbers.

Here are the 4 zsh plugins I use with the profiling features enabled:

zmodload zsh/zprof

. "${XDG_DATA_HOME}/fast-syntax-highlighting/fast-syntax-highlighting.plugin.zsh"
. "${XDG_DATA_HOME}/zsh-autosuggestions/zsh-autosuggestions.zsh"
. "${XDG_DATA_HOME}/zsh-vi-mode/zsh-vi-mode.plugin.zsh"
. "${XDG_DATA_HOME}/fzf-tab/fzf-tab.plugin.zsh"

zprof

Here's zprof with all 4 plugins enabled:

num  calls                time                       self            name
-----------------------------------------------------------------------------------
 1)    1          21.57    21.57   74.93%     21.57    21.57   74.93%  zvm_exist_command
 2)    1           4.12     4.12   14.32%      4.12     4.12   14.32%  _zsh_highlight_bind_widgets
 3)    1           2.21     2.21    7.69%      2.21     2.21    7.69%  enable-fzf-tab
 4)    2           0.31     0.15    1.06%      0.31     0.15    1.06%  add-zsh-hook
 5)    1           0.22     0.22    0.78%      0.22     0.22    0.78%  is-at-least
 6)    1           0.16     0.16    0.56%      0.16     0.16    0.56%  (anon) [/home/nick/.local/share/zsh-autosuggestions/zsh-autosuggestions.zsh:460]
 7)    1           0.12     0.12    0.42%      0.12     0.12    0.42%  (anon) [/home/nick/.local/share/fzf-tab/fzf-tab.zsh:398]
 8)    1           0.04     0.04    0.13%      0.04     0.04    0.13%  -fast-highlight-fill-option-variables
 9)    1           0.03     0.03    0.12%      0.03     0.03    0.12%  (anon) [/home/nick/.local/share/fast-syntax-highlighting/fast-highlight:35]

My end to end time is ~140ms:

$ time zsh -i -c exit
zsh -i -c exit  0.03s user 0.02s system 41% cpu 0.140 total

Here's zprof except I commented out this plugin:

num  calls                time                       self            name
-----------------------------------------------------------------------------------
 1)    1           4.27     4.27   55.94%      4.27     4.27   55.94%  _zsh_highlight_bind_widgets
 2)    1           2.46     2.46   32.19%      2.46     2.46   32.19%  enable-fzf-tab
 3)    2           0.30     0.15    3.93%      0.30     0.15    3.93%  add-zsh-hook
 4)    1           0.24     0.24    3.14%      0.24     0.24    3.14%  is-at-least
 5)    1           0.18     0.18    2.32%      0.18     0.18    2.32%  (anon) [/home/nick/.local/share/zsh-autosuggestions/zsh-autosuggestions.zsh:460]
 6)    1           0.11     0.11    1.48%      0.11     0.11    1.48%  (anon) [/home/nick/.local/share/fzf-tab/fzf-tab.zsh:398]
 7)    1           0.04     0.04    0.51%      0.04     0.04    0.51%  -fast-highlight-fill-option-variables
 8)    1           0.04     0.04    0.48%      0.04     0.04    0.48%  (anon) [/home/nick/.local/share/fast-syntax-highlighting/fast-highlight:35]

My end to end time is ~80ms:

$ time zsh -i -c exit
zsh -i -c exit  0.04s user 0.01s system 59% cpu 0.081 total

I'm not sure if zprof reports milliseconds but it's certainly adding more than 21ms of delay. The end to end time difference is +60ms (140 - 80). It's really noticeable because I have a feeling something else is causing even more of a delay that's not picked up in these tests. It feels like 200-300ms before the prompt is ready.

Any thoughts on how to troubleshoot what's causing this slowdown?