License text for LGPL-3.0
This is a follow-up from the discussion last summer at , based on the conversation during the Legal Team call this past week.
Folks may want to re-read the (long) thread there, which has links to the (long) discussion  in 2019-2020 and the (long) original conversation in 2015.
Assuming you don't want to, here's the gist of last week's conversation followed by the concrete proposal that was discussed.
(Note: all of the following applies to both the "-only" and "-or-later" variants of LGPL-3.0 and GPL-3.0, as well as the deprecated IDs that don't use either suffix.)
* The license-list-XML repo includes plain text versions of each license  which are primarily used to test whether the license's XML template matches the expected text.
* Some downstream projects, organizations and individuals, including REUSE , use these plain text license files as a source for obtaining and reproducing the license's text, e.g. to insert into a repo's license documentation. Although this wasn't an original design goal for the License List, some folks are doing it and finding value in it.
* For most licenses this approach works well, but for LGPL-3.0 it causes issues. LGPL-3.0 incorporates the text of GPL-3.0 by reference, but the LGPL-3.0 XML template  and text file  only contain the LGPL's own text, not the GPL's. So someone using this approach would only end up with LGPL's text.
* Traditionally the FSF has recommended that the LGPL and GPL text both be included in a repo, but in separate files.  SPDX doesn't have a way to represent that contents of multiple files should correspond to a single license.
* More recently (I believe following discussions with REUSE project participants), the FSF has subsequently published a version with the LGPL-3.0 text immediately followed by the GPL-3.0 text in a single file. , see 
REUSE would like to see the combined LGPL-3.0 + GPL-3.0 text used as the plain text file for LGPL-3.0 on the License List. That way, anyone pulling from the plain text licenses will (correctly) include both the LGPL and GPL texts.
To implement this, the XML template for LGPL-3.0 would also be updated, to add the GPL-3.0 text with <optional> tags following the non-optional LGPL-3.0 text.
Personally, I'm +1 to make these changes:
* It solves the problem REUSE has identified for their use case
* It means that the LGPL-3.0-* templates will continue to match standalone files with only the LGPL text, as well as matching files that contain the combined LGPL+GPL texts.
* It doesn't resolve all possible ambiguities about "did you mean everything in this repo is LGPL, or that some things are LGPL and some are GPL?" But neither does the current state of affairs. Using SPDX short-form license IDs and/or standard license headers solves this. So I don't see this as particularly significant to this specific proposal.
Things that are off-topic for this thread:
* whether LGPL-3.0 should have been an "exception" rather than a "license" (see ,  and )
* whether this was an ideal way for LGPL-3.0 to have been drafted (see the same threads)
Final side note:
I'd like to recognize Jilayne for accurately predicting that we'd be having this conversation right now, give or take a couple of months. 
 https://github.com/spdx/license-list-XML/tree/master/test/simpleTestForGenerator; in license-list-data repo at https://github.com/spdx/license-list-data/tree/master/text
 https://www.gnu.org/licenses/gpl-howto.html, see "COPYING" and "COPYING.LESSER"