A more accurate DA1 report
The purpose of the DA1
(primary device attributes) report is to describe the functional capabilities of the terminal. However, VTE's current DA1
response implies that it has features which aren't actually supported. It would helpful to apps if this reporting could be made a little more accurate.
In case you aren't aware, the first parameter of the report indicates the base conformance level. The remaining parameters identify any optional extensions. Terminals reporting a given level are expected to support all the controls defined for that level and below. And at the higher levels, certain extensions become mandatory, where they may have been optional before.
VTE currently reports conformance with level 5 (parameter value 65). This implies that it supports things like selective erase, user-defined keys, the status display, rectangular editing, text macros, paging, and more. In reality it supports none of those things.
To be more accurate, it shouldn't really be claiming anything higher than level 1 conformance (i.e. 61 as the first parameter). But you can still then add on the various extensions that are actually supported. I think that would include the following:
1 - 132 column mode
4 - sixel graphics (when enabled)
21 - horizontal scrolling
22 - color text
As far as I'm aware, VTE doesn't support the NRCS feature (extension 9), which it's currently reporting.
If you want to continue identifying as a VT525 in DA2
(the secondary device attributes report), that's probably not a big deal. Apps shouldn't be using that for feature detection anyway.