在线阅览器支持所有标准的PDF注释/标记工具，但有一些限制。
在线查看器支持以下标准的 PDF 注释和标记工具：
请参阅我们的在线阅览器快速指南，了解可用标记的完整列表。
While the Online Viewer is compatible with commonly used markup tools, we continue working towards increasing our support.
Any extended markups (not listed above) created using third-party applications, such as Adobe reader, PDFCreator, or Bluebeam may result in compatibility issues when viewed in the Online Viewer. As an example, a dotted arrow produced in Bluebeam will be visible as a solid arrow in the Viewer.
Adobe Markup tools currently unsupported are:
We recommend you avoid using these tools until we provide support for them, as they will not be recognized by the Online Viewer. Use the annotation and stamps tools as an alternative to Fill & Sign.
An Interactive PDF allows users to add/edit data within a PDF using components such as hyperlinks, checkboxes, radio buttons, dropdowns, and text entry fields.
The Online Viewer will open interactive PDFs for viewing, but support for marking up within them is limited.
Text entered in a text field can be only be saved if an additional Viewer markup is added to the PDF before saving.
This workaround applies only for Text fields. Values selected in other components such as radio buttons and drop-down boxes cannot be saved.
