CHAT--Change Size of Type
I noticed that if you bring up Chat (on the Mac) you can hold down the command key and click on the plus or minus to change the size of the type. Alan brought up a good point, as this does not work on the PC. Does it work on the PC some other way? I could not make that work on an iPhone or iPad as I have no idea how to hold down a key on either device. Maybe someone else knows. Making Chat a Pop-Out also helps to enlarge the Chat screen itself. Helpful for low-vision folks!

CHAT--Save Chat
Just a reminder that you can save chat: Open Chat; Click on bottom right 3 dot menu; Save Chat. (I do not see that option on the iPhone or iPad.) I do believe that also works on the PC.
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You can increase/decrease the font size in the chat window when there are closed captions. From the CC icon, CC > Subtitle Settings > Accessibility > Chat Display Size. 
If there aren't closed captions, go to your video settings (use the caret next to the video camera icon) and then Accessibility.
When I started a Zoom meeting, I was able to use the Control +/- as a host. I wasn't able to do so as a co-host or participant. I am using a PC desktop with W10.
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Alan Katsura
Moderator HLAA Tech Group

ANOTHER TIP: There is a setting where Chat saves automatically, when you end the meeting.

 Enter in Google:  www.zoom.us

 Log in with ID and Password

 Click on My Account in upper right corner

 On left menu, go to Settings:
In Meeting (Basic) it says:

Auto saving chats

Automatically save all in-meeting chats so that hosts do not need to manually save the text of the chat after the meeting starts.-