Openbox/tint2

#-------------------------------------
# Tooltip
tooltip = 0
tooltip_show_timeout = 0
tooltip_hide_timeout = 0.1
tooltip_padding = 2 2
tooltip_background_id = 3
tooltip_font_color = #efefef 100
tooltip_font = Noto Sans 8

#---- Generated by tint2conf 581b ----
# See https://gitlab.com/o9000/tint2/wikis/Configure for
# full documentation of the configuration options.
#-------------------------------------
# Backgrounds
# Background 1: Normal task, Panel, Systray
rounded = 0
border_width = 0
background_color = #252525 100
border_color = #efefef 30
background_color_hover = #000000 60
border_color_hover = #000000 30
background_color_pressed = #000000 60
border_color_pressed = #000000 30

# Background 2: Iconified task
rounded = 4
border_width = 1
background_color = #000000 20
border_color = #777777 30
background_color_hover = #aaaaaa 22
border_color_hover = #eaeaea 44
background_color_pressed = #555555 4
border_color_pressed = #eaeaea 44

# Background 3: Active task, Tooltip
rounded = 4
border_width = 1
background_color = #252525 100
border_color = #fbfbfb 58
background_color_hover = #6d6868 76
border_color_hover = #f9f2f2 64
background_color_pressed = #555555 4
border_color_pressed = #eaeaea 44

# Background 4: Urgent task
rounded = 4
border_width = 1
background_color = #aa4400 100
border_color = #aa7733 100
background_color_hover = #cc7700 100
border_color_hover = #aa7733 100
background_color_pressed = #555555 4
border_color_pressed = #aa7733 100

# Background 5: Inactive desktop name, Inactive taskbar, Launcher
rounded = 1
border_width = 0
background_color = #030000 100
border_color = #000000 100
background_color_hover = #ffffff 100
border_color_hover = #000000 100
background_color_pressed = #ffffff 100
border_color_pressed = #0b94f4 100

#-------------------------------------
# Panel
panel_items = TS
panel_size = 100% 29
panel_margin = 0 0
panel_padding = 2 2 2
panel_background_id = 1
wm_menu = 1
panel_dock = 0
panel_position = top center horizontal
panel_layer = top
panel_monitor = all
primary_monitor_first = 0
autohide = 0
autohide_show_timeout = 0
autohide_hide_timeout = 0
autohide_height = 2
strut_policy = follow_size
panel_window_name = tint2
disable_transparency = 1
mouse_effects = 1
font_shadow = 1
mouse_hover_icon_asb = 92 -2 10
mouse_pressed_icon_asb = 100 0 0

#-------------------------------------
# Taskbar
taskbar_mode = single_desktop
taskbar_padding = 2 0 2
taskbar_background_id = 5
taskbar_active_background_id = 0
taskbar_name = 0
taskbar_hide_inactive_tasks = 0
taskbar_hide_different_monitor = 0
taskbar_always_show_all_desktop_tasks = 0
taskbar_name_padding = 5 0
taskbar_name_background_id = 5
taskbar_name_active_background_id = 0
taskbar_name_font = Noto Sans 8
taskbar_name_font_color = #e3e3e3 100
taskbar_name_active_font_color = #efefef 100
taskbar_distribute_size = 0
taskbar_sort_order = none
task_align = left

#-------------------------------------
# Task
task_text = 0
task_icon = 1
task_centered = 1
urgent_nb_of_blink = 100000
task_maximum_size = 38 28
task_padding = 1 1 4
task_font = Noto Sans 8
task_tooltip = 0
task_urgent_icon_asb = 100 0 0
task_normal_background_id = 1
task_active_background_id = 3
task_urgent_background_id = 4
task_iconified_background_id = 2
mouse_left = toggle_iconify
mouse_middle = none
mouse_right = close
mouse_scroll_up = toggle
mouse_scroll_down = iconify

#-------------------------------------
# System tray (notification area)
tooltip = 0
systray_padding = 2 2 3
systray_background_id = 1
systray_sort = ascending
systray_icon_size = 35
systray_icon_asb = 0 0 10
systray_monitor = 1

#-------------------------------------
# Launcher
launcher_padding = 2 10 2
launcher_background_id = 5
launcher_icon_background_id = 0
launcher_icon_size = 20
launcher_icon_asb = 100 0 0
launcher_icon_theme = nouveGnomeGray
launcher_icon_theme_override = 1
startup_notifications = 1
launcher_tooltip = 1
launcher_item_app = /usr/share/applications/tint2conf.desktop
launcher_item_app = /usr/local/share/applications/tint2conf.desktop
launcher_item_app = /usr/share/applications/firefox.desktop
launcher_item_app = /usr/share/applications/iceweasel.desktop
launcher_item_app = /usr/share/applications/chromium-browser.desktop
launcher_item_app = /usr/share/applications/google-chrome.desktop

#-------------------------------------
# Clock
time1_format = %H:%M
time2_format = %A %d %B
time1_font = Noto Sans 8
time1_timezone =
time2_timezone =
time2_font = Noto Sans 8
clock_font_color = #efefef 100
clock_padding = 2 0
clock_background_id = 0
clock_tooltip = 0
clock_tooltip_timezone =
clock_lclick_command =
clock_rclick_command =
clock_mclick_command =
clock_uwheel_command =
clock_dwheel_command =

#-------------------------------------
# Battery
battery_tooltip = 0
battery_low_status = 10
battery_low_cmd = notify-send "battery low"
bat1_font = Noto Sans 8
bat2_font = Noto Sans 8
battery_font_color = #efefef 100
battery_padding = 3 2
battery_background_id = 0
battery_hide = 101
battery_lclick_command =
battery_rclick_command =
battery_mclick_command =
battery_uwheel_command =
battery_dwheel_command =
ac_connected_cmd =
ac_disconnected_cmd =

#-------------------------------------
# Tooltip
tooltip = 0
tooltip_show_timeout = 0
tooltip_hide_timeout = 0.1
tooltip_padding = 2 2
tooltip_background_id = 3
tooltip_font_color = #efefef 100
tooltip_font = Noto Sans 8

# Tooltips
tooltip = 0
tooltip_padding = 2 2
tooltip_show_timeout = 0.7
tooltip_hide_timeout = 0.3
tooltip_background_id = 1
tooltip_font = sans 10
tooltip_font_color = #000000 80

# Tooltips
tooltip_padding = 2 2
tooltip_show_timeout = 0.7
tooltip_hide_timeout = 0.3
tooltip_background_id = 1
tooltip_font = sans 10
tooltip_font_color = #000000 80

Koluchka
Насколько я понимаю, в трее всплывающие подсказки выводит не панель, а сами приложения, значки которых висят в трее. И оформление этих тултипов зависит от приложения, темы qt или gtk, а не от панели.