Don’t waste your time with the gmail app. Give a try to the Microsoft Outlook app, it's probably the best app for managing gmail. Updated for the new iPad Pro aspect ratio and fully compatible with split view. After testing it, I’m not going back.
Thanks, but Outlook is not for me.
I admire the fact that it quickly gets updated for new OS features, but every time I use it for a bit - and I'd like to, as it has a reasonable (but super buggy) Watch app - I too often have problems with cut and pasting, emails not arriving in a timely matter, issues with attachments etc. Can't remember the specifics, but I had one particular recurring problem that I emailed the devs about. They responded directly, to their credit. Sent them a video of it happening, they acknowledged the issue but couldn't fix it as they couldn't replicate it. Tried all the usual procedures, fresh installs, different accounts blah blah, different devices, but it never got fixed oddly.
I want to use Outlook, but when I periodically give it another ago I end up disappointed. The Gmail app is frankly pathetic, but for the fairly simple usage case I have its always been completely reliable.