Re: "I am getting emails that have attachments but they don't show as icons
I know where to look—overing over the line beneath he addresses— .."
Am still using Ventura, yet am mostly seeing that same attachment situation.
Here is some of the info. available for Sonoma,.
Most of it you are likely quite familiar with, but you may want to use some of the options:
"View email attachments
- In the Mail app
on your Mac, select a message that includes attachments. - Look for the Attachment icon
below the date the message was sent in the message list. - In the message, do one of the following:
- Open an attachment in an app: Double-click the attachment.
- Preview an attachment without opening it: Select the attachment, then press the Space bar, or force click the attachment.
Some attachments — like images or one-page PDF documents — are displayed directly in the message.
If you’d rather view the attachment as an icon, Control-click it, then choose View as Icon from the shortcut menu. To display the attachment again, Control-click it, then choose View in Place."
More info: View, save, or delete email attachments in Mail on Mac - Apple Support
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Re: " -- but an attachment icon should simply be visible, rather than me having to go look for it".
"Mail automatically downloads attachments you receive based on the download option you set in
"Account Information settings" in Mail."
Mail always downloads media attachments (such as image, PDF, video or audio files) that you receive.
To have Mail automatically download other types of attachments (such as spreadsheets or zipped files),
choose Mail > Settings, click Accounts, then click Account Information:
click the pop-up menu, then choose an option:
All: Mail always downloads these attachments.
Recent: Mail downloads only attachments of this type received within the past 15 months.
None: Mail doesn’t download any of these attachments.
Mail downloads attachments you receive to a special folder in your home Library folder."
More info: Account Information settings
If you wish, there's a: Web-form online for feedback to Apple (link below):
Feedback - Mail - Apple
All the best :-)