Glitchy.
During long periods of editing documents, it gets glitchy. Turns text to funky characters. Side tool bars get distorted. Then crashes suddenly. Today I worked for 6 hours on a proposal, even making sure I saved it every once and a while to be sure it didn't happen. Guess what! It happened and I lost everything except the part of the document I started with this morning.
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Sorry for the inconvenience caused to you.
If this happens with multiple PDF opened with Adobe Acrobat/Reader, then you may try the troubleshooting steps given below-
• Install the latest update of Adobe Reader. Open Reader>Help>Check for update or refer to- https://www.adobe.com/devnet-docs/acrobatetk/tools/ReleaseNotesDC/index.html
• If this doesn’t help, then Open >Help>Repair Installation.
• If you still face issue, then you may uninstall the application using cleaner tool-https://labs.adobe.com/downloads/acrobatcleaner.html