Commenting allows you to make markings and comments in files and upload them back to the system:
Depending on the project configuration, commenting is done either directly in the browser or with an external PDF Viewer. Which method of commenting is used in your project is designated by the Project Administrator.
The option to comment files is also available in the CC-Files app.
To make comments to a file stored within the system, click on the icon next to the filename.
Depending on the assigned method of commenting in the project the file will either open directly in you browser or it is downloaded to you device and can be commented using an external PDF program.
Open the file by clicking on the icon next to the filename. The file will open in a new tab of your browser:
Comment
Use the options at the top as required to adjust, add comments and markings by clicking on the icon or show the list of comments by clicking on the left:
Move / Size / Rotate (Right-click in the document for the menu with additional options)
Select
Add forms (click the arrow for additional options: Circle / Line / Arrow / Polygon / Cloud)
Add note
Freehand draw
Textbox with arrowline (callout) / Textbox
Highlight / Cross out / Underline / squiggly underline / Write text
Properties
To access the properties of individual comments, right-click on the comment and select "Properties":
Once in the properties you can then adjust the color, outline, font etc. as desired:
No changes can be made under "Properties" once a comment has been saved to the system.
Stamps
Add personalized stamps when you click on the stamp icon
The icon for stamps becomes available in the options at the top after a stamp has been uploaded under "My profile".
To add stamps, click on the username / icon in the top right and select "My profile": 
Upload stamps (format: PDF/PNG/JPG) to be used for commenting on the "My profile" page under the tab "Stamps"
Video: How to Upload and Use Stamps
Save
To relay the comments back to the system, click on the disc-symbol at the top of the page:
Once the upload is completed successfully, there will be a notification at the bottom of the page:
Open the file by clicking on the icon next to the filename.
This will download the file to your hard drive where you can open it with the appropriate PDF-Viewer.
Open the file and make your comments, then upload the file by clicking on the logo
in the top left-hand corner of the page.
To make comments in the CC-Files app, download the file in the app and then click on the filename to open.
Once the file is open, click on the pencil icon at the bottom to show the commenting options:
Click on the option to use and then click on the placement in the document to insert.
Options for commenting are:
Add note
Draw & comment (click and hold icon for further options: ie textbox, highlight, cross-out, underline)
Draw lines (click and hold icon for further options: lines / arrows / squares / circles)
Erase
Reverse last step / Close options
Once all comments have been made you can upload them directly to the system by clicking at the bottom
Further Options at the bottom:
Help
Share
Hide / Show comments
Table of all comments
Check for new comments
Upload comments
File information
Once the comments have been uploaded successfully either via app, browser or external pdf-viewer, the filename will appear in red to indicate that this is a file containing comments. Each download of the file will also contain the comments, there is however also the option to select the file and choose "Download without Redlining" from the menu at the bottom:
All markups are also listed under the tab "Redlining" in the file information:
The author of the markups may also delete them by clicking on the in front of the entry.