The View menu sets how the session is seen, and what's visible or not.

[] Maximise Editor Space
Puts the Editor window in full screen mode
[] Maximize Mixer Space
Puts the Mixer window in full screen mode
Primary Clock
Focus On Clock
Sets the focus on the main clock, allowing to type in numbers directly to change the playhead position
Timecode
Sets the main clock in timecode mode, so it displays time in the Hours:Minutes:Seconds:Frames format
Bars & Beats
Sets the main clock in musical time mode, so it displays time in the Bars:Beats:Ticks format
Minutes & Seconds
Sets the main clock in absolute time mode, so it displays time in the Hours:Minutes:Seconds.Milliseconds format
Samples
Sets the main clock in samples time mode, so the time is displayed in samples from the absolute start
Secondary Clock
Timecode
Same as for the main clock (see above)
Bars & Beats
Same as for the main clock
Minutes & Seconds
Same as for the main clock
Samples
Same as for the main clock
Zoom
Zoom In
Zooms in, focusing the Zoom Focus (see below)
Zoom Out
Zooms out
Zoom to Session
Adjust the zoom value so that all the session (as defined by its start and end markers) fit in the window
Zoom to Selection
Adjust the zoom value so that all the selected regions fit in the window
Fit Selection (Vertical)
Fits the selected track(s) in the window. If too many tracks are selected, they'll be reduced to their minimum height.
Toggle Zoom State
Reverts to last zoom state (kind of "undo" for zoom, even if edits have been made inbetween)
Expand Track Height
Increases the height of the selected tracks. If no track is selected, then all the tracks are expanded
Shrink Track Height
Same as above, but reduces the height of the tracks
Zoom Focus
Zoom Focus Left
Sets the screen's left side as the zoom target, i.e. when zooming in, the left side of the screen will stay at the same place in the timeline
Zoom Focus Right
Same, with the right of the screen
Zoom Focus Center
Same, with the center of the screen
Zoom Focus Playhead
Sets the playhead as the focus point of the zoom, i.e. the point in time that will stay fixed
Zoom Focus Mouse
Same as above, with the mouse pointer
Zoom Focus Edit Point
Same as above, with the Edit Point
Next Zoom Focus
Circles between the previous modes
Rulers
[] Min:Sec
Showss (when checked) or hides a line in the Ruler with the time formatted as Hours:Minutes:Seconds.Milliseconds
[] Timecode
Same as above, with the time formatted as Hours:Minutes:Seconds:Frames
[] Samples
Same as the above, with the time displayed in samples from the absolute start
[] Bars & Beats
Same as the above, with the time formatted as Bars:Beats:Ticks
[] Meter
Shows / hides the Meter line in the ruler, where the signature can be adjusted along the playline
[] Tempo
Shows / hides the Tempo line, where the BPM can be changed with markers
[] Ranges
Shows / hides the Range line, where ranges can be defined
[] Loop/Punch
Shows / hides the Loop/Punch line, where loops and Punches can be defined
[] CD Markers
Shows / hides the Range line, where CD Markers can be defined
[] Markers
Shows / hides the Markers line, where custom markers can be defined
[] Video
Shows / hides the Video timeline, where frames of the video are shown for syncing purposes
Video Monitor
Original Size
When the Video Monitor is active, resets its size to the original size, i.e. 1 pixel in the video is 1 pixel on screen
[] Letterbox
When checked, forces the ratio (width/height) to be the one of the original video. If unched, the video will be stretched to fit the window
[] Always on Top
Stays above all other windows, enabling to work in Ardour without the video windows to be hidden in the background
[] Fullscreen
Sets the Xjadeo window to be fullscreen. Can be usefull in a dual monitor setup
[] Timecode
When checked, displays a Timecode over the video, in the Hours:Minutes:Seconds:Frames format
[] Frame number
When checked, shows the absolute frame number inside the video, i.e. this image is the nth of the video
[] Timecode Background
Adds a black background to the timecode for readability
Scroll
Scroll Tracks Down
Scrolls the view toward the bottom of the session from one screen (vertically, so along tracks)
Scroll Tracks Up
Same as above, towards the top
Scroll Forward
Scrolls the view toward the right of the session from one screen (horizontally, so along time)
Scroll Backward
Same as above, to the left
Views
Save View n
Saves the position on the timeline in the memory, horizontally and vertically (along time and tracks)
Go to View n
Loads and displays a saved position (see above)
[] Show Editor Mixer
When checked, the selected tracks' mixer strip is displayed on the left of the editor window, allowing for a quick access to e.g. efffects and routing
[] Show Editor List
In the Editor window, shows the Editor List, giving access to a number of handy lists (regions, tracks, …)
[] Toggle Mixer List
In the Mixer view, shows the Mixer list, giving access to some handy lists (Favorite plugins, The Strip list,…)
[] Toggle Monitor Section Visibility
If the Use monitoring section on this session has been checked in the Session Properties window, shows pr hide the Monitor Section in the Mixer
[] Show Measure Lines
If checked, in the Editor, shows a vertical white lines at each measure start
[] Show Summary
If checked, in the Editor, shows the Summary, allowing a faste navigation in the session
[] Show Group Tabs
If checked, makes the groups visible as tabs on the left in the Editor, and on the top in the mixer
[] Show Marker Lines
If checked, each marker is extended across all the tracks in the editor with a line of the same color