Extension (manifest v. 3) runs fine on desktop Firefox, but not on the Android Nightly

My extension, which runs manifest version 3, runs great on the desktop version of the browser, but when I installed it on the current Nightly Firefox, it seems to install OK, but when I tap on the icon, a signin screen should be displayed, like it does on desktop Firefox, but nothing happens. I manually set the Storage permissions with Android settings, so that shouldn’t be the problem. web-ext lint returned one error and five warnings:

ruomini@ruomini-XPS-13-9370:~/Downloads/Firefox/dist$ web-ext lint
Validation Summary:

errors 1
notices 0
warnings 6

ERRORS:

Code Message Description File Line Column
JS_SYNTAX_ERROR JavaScript There is a JavaScript web-ext.js 3 1
syntax syntax error in your
error code, which might be
(Parsing as related to some
module experimental
error: JavaScript features
Unexpected that aren’t an
character official part of the
‘!’ at language specification
line: 1 and and therefore not
column: 2) supported yet. The
(Parsing as validation cannot
script continue on this file.
error:
‘import’
and
‘export’
may appear
only with
‘sourceTyp…
e: module’
at line: 3
and column:
1)
WARNINGS:

Code Message Description File Line Column
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security assets/ind… 1 1004
assignment and performance ex.c9f9fbc…
to concerns, this may not 5.js
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security assets/Lis… 12 3332
assignment and performance t.859b5700…
to concerns, this may not .js
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security assets/Lis… 90 216
assignment and performance t.859b5700…
to concerns, this may not .js
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security content/ma… 2868 60489
assignment and performance in.js
to concerns, this may not
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security content/ma… 2879 3332
assignment and performance in.js
to concerns, this may not
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.
UNSAFE_VAR_ASSIGNMENT Unsafe Due to both security content/ma… 2957 216
assignment and performance in.js
to concerns, this may not
innerHTML be set using dynamic
values which have not
been adequately
sanitized. This can
lead to security
issues or fairly
serious performance
degradation.